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The encapsulation and delivery of drugs often involves the use of expensive microporous materials, and we have investigated the potential for natural zeolites from the widespread volcanic formations of southern Italy as alternatives to these carriers. Surface-modified natural zeolites (SMNZs) with diverse micellar structures (patchy and complete bilayers) were obtained by using different cationic surfactants [cetylpyridinium chloride (CP-Cl), benzalkonium chloride (BC-Cl), hexadecyltrimethylammonium chloride (HDTMA-Cl), and bromide (HDTMA-Br) with phillipsite-rich tuff from the Campania region (southern Italy)]. Loading and release kinetics tests of sodium ibuprofen (IBU) were carried out with organo-phillipsite composites using Fourier transform infrared spectroscopy (FTIR) and thermal analysis coupled with evolved gas analysis (EGA). Results from these tests were mathematically modeled to evaluate IBU adsorption and release mechanisms. The maximum loaded amount of IBU was attained for organo-phillipsite modified with HDTMA-Br (PHB), which showed a complete bilayer micellar structure. Whenever a patchy bilayer micellar structure formed, the lowest adsorptions of IBU were observed. Equilibrium adsorption results were fit using Langmuir, Sips, and Toth models. Pseudo-first-order and pseudo-second-order fits to the loading kinetic data provided significant goodness of fit. Good fits to the release kinetic data were obtained using first-order and Weibull equations, shedding new light on the release mechanism of IBU from phillipsite. The active amount of IBU on the modified zeolite surface was almost totally available for pharmaceutical purposes.

At Positano, the renowned town of the Amalfi coast (Salerno province), a Roman villa was found beneath the church of Santa Maria Assunta. It likely dates back to I century BC - I century AD (Julio-Claudian age) and belonged to the freedman Posides Claudi Caesaris, from whose the town might probably derive the name (Della Corte, 1936). The villae were prestigious residences disseminated as status symbol of the wealthy Roman people all around the coastal areas of the Campania region (i.e. Vesuvian villae; Maiuri, 1955. Guzzo & Guidobaldi, 2008). During the 79 AD eruption of the Vesuvius the residence was suddenly destroyed and covered by a volcanoclastic debris flow more than 10 m thick, composed of a mass of gray ashes with large amount of high-porosity welded pumices. During the Middle age, Benedictine monks built an abbey on the same site of the Posides’ villa, then transformed in the present church dedicate to the Virgin. At the beginning of the 2000, the Archaeological Superintendence started the recovery of the overlying Benedictine crypts and extended the excavation and recovery also downward to the villa remains. Inside the crypts it was possible to unearth, descending in the villa from tiles roof till to mosaic pavement, a luxurious triclinio. Imprints of holes related to large wood poles (now replaced with plaster casts), as well as fragments of the roof, coffered ceiling, doors and other wooden remains were found embedded in the volcanoclastic mud. Tuff walls are decorated with fine plasters, polychrome frescoes of excellent painters, with hippocampus, eagle poised upon a globe, Pegasus and Cupids. These lively compositions are basically made by some colors, like the “Pompeian” red, blue and yellow ochre. This work reports a preliminary archaeometric study of various artifacts from the Positano villa, represented by plasters, fresco fragments, tile and other materials. Small but representative samples of the different findings were analyzed, in order to reach our characterization scopes and to provide useful information on probable future restoration activities. The analytical techniques used for mineralogical and petrographic study are: optical and stereoscopic studies on thin sections, modal analysis, X-ray powder diffraction (XRPD), scanning electron microscopy analysis (SEM) and energy-dispersion X-ray spectroscopy (EDS). Data concerning the composition of the artifacts and manufacturing techniques will be reported and compared with the reference literature. Della Corte M. 1936. Posides Claudi Caesaris libertus – Positano da Posidetanum? Rivista Indo-greca-Italica, 20, 67-73 Guzzo P.G. & Guidobaldi M.P. 2007. Nuove ricerche archeologiche nell'area vesuviana (scavi 2003-2006). Atti Conv. Int. Roma 1-3 febbraio, L’Erma di Bretschneider, 629 p. Maiuri A. 1955. Le vicende dei monumenti antichi della costa amalfitana e sorrentina alla luce delle recenti alluvioni. Rend. Acc. Arch. Lett. Belle Arti Napoli, XXIX, 87-98.

X-ray Diffractometry is a very useful analytical technique to achieve detailed information about the crystal structure and mineralogical composition, qualitative and quantitative, of matter. It is a technique that exploits the interaction between solid matter and X-rays that, converged on a substance, are diffracted. The outgoing X-rays, on the basis of the wavelength of the incident beam and according to the path within the analyzed sample provide information on fundamental param- eters of the crystalline state as the distance of the lattice planes and the parameters of the elementary cell. The analytical result is called diffraction pattern containing a series of peaks that show the intensity and angular position of the diffracted X-rays. Typically, a diffraction pattern represents, for individual minerals, a kind of distinct fingerprint and can be used to easily identify the material or distinguish it from others, especially with the use of modern databases. X-Ray Diffractometry can be successfully used in a variety of fields: building materials, geological sam- ples, environmental pollutants and increasingly by forensic sciences as a scientific aid for the analysis of evidence from crime scenes.

This research is based on the characterization of ancient mortars from the Anfiteatro Flavio (Pozzuoli) dating back to the 1st and 2nd century CE through a multi-analytical approach involving macroscopic, mineralogical, petrographic, and chemical investigations. The goal that has been set is to deepen knowledge about mortar mix design, the provenance of used raw materials, and secondary minerogenetic processes that have occurred within ancient Roman mortars. Results show that: (i) raw materials for mortar preparation have a local provenance, i.e., Phlegraean Fields area; (ii) mortars can be considered as hydraulic; (iii) calcite presence could be due to a non-complete calcination process, an improper slaking or to exposition of materials to the subaerial environment; (iv) gypsum is due to calcite sulfation process; (v) halite presence is due to marine aerosol exposition. The achieved information testifies that, for at least two centuries, Roman builders considered the identified mortar mix as optimal for their buildings, but also contributes to the understanding of their technical skills and represents an important first step to planning future restoration operations.

The purpose of this study is to evaluate different lightweight concretes for the first time formulated with lightweight expanded aggregates produced only with industrial waste. The motive is that a lack of knowledge still exists in the literature about how to integrate these waste-based aggregates in lightweight concrete. To achieve the desired bloating and aggregates physical properties, PC-TV screen glass and ceramic tile polishing sludge were selected as suitable raw materials. Both were characterized by mineralogical and chemical analyses and the effect of different combinations was pointed out. Hot-stage microscopy was used to determine the bloating rates and firing behavior. Lightweight expanded aggregates were obtained using both static laboratory kiln and rotating pilot kiln, by firing at maximum temperatures between 1150 and 1200 ◦C, to simulate the industrial production process and favor scaling up. The so obtained aggregates were characterized from the physical-mechanical point of view, highlighting an important bloating attitude and bulk density lower than 700 kg/m3 for all the test conditions. Bulk density, water absorption and mechanical properties are fully comparable to commercial counterparts. The best material was used as coarse aggregate in lightweight structural concrete and cellular concrete prepared at pilot scale (for structural application and thermal/acoustic insulation, respectively). The technical properties are consistent with standard requirements of compressive strength (>25 MPa for lightweight structural concrete) and thermal conductivity (18–24 W/m*K for cellular concrete). These results demonstrate the technological feasibility of using waste-based aggregates into lightweight concrete design, according to a circular economy vision.

A Roman luxury villa (1st century BC) was discovered in the town of Positano, in the Sorrento peninsula (Campania region, southern Italy). Despite being more than 20 km away from Vesuvius, the villa was buried under almost overall 20 meters (total thickness) of pyclastic materials of the Plinian eruption of 79 AD, which destroyed Pompeii and Herculaneum towns. The exceptional level of conservation of this residential complex is due to the peculiar burial process, which determined the excellent state of preservation of both the fresco decorations (Fourth Style) and all other artefacts (masonries, plasters, tiles, furnishing remains, wooden elements, kitchenware, glazed oil lamps, bronze vessels and other metallic findings, etc.). This study presents the results of a multi-analytical archaeometric analysis of plasters, fresco pigments and roof tiles, aimed at identifying their mineralogical and petrographic nature and the provenance of raw materials. Constraints to the geoarchaeological landscape of the Positano area are also given. The analyzed plasters are mainly lime-based, usually with the addition of an aggregate. The anchoring layer is made by a volcanic component, characterized by clinopyroxene, alkali feldspar, garnet, amphibole, biotite and leucite crystals, together with a sedimentary component represented by carbonatic fragments, also with traces of microfossils. The features of plasters confirm the high degree of technological standardization of plasters in classical Roman age. Mineral pigments recognized by preliminary XRD are mainly iron-based for the ochers-red-crimson colors and copper-based for green-blues colors. In the roof tiles two kind of tempers are identified. In three samples a volcanic temper was identified, and represented by clinopyroxene, feldspar, garnet and leucite, whereas the temper of a fourth sample contained pumices with minor amounts of alkali feldspar, clinopyroxene and biotite. The raw materials are of local provenance (Somma-Vesuvius, Phlegraean Fields, Apennine limestones), and the microstructure of the materials are comparable with similar artefacts from Pompeii, Herculaneum and other Roman sites in Campania region. On the basis of geoarchaeological investigations, here reported, it is reasonable to think that there are other unearthed archaeological areas in Positano that will require further study to be properly known

GDS;VJ Tech, 4th European Conference on Unsaturated Soils, E-UNSAT 2020 -- 19 October 2020 through 21 October 2020 -- -- 164161, In soil stabilisation, the use of alternative products to lime or cement has been proposed. However, the effects of these additives, of various origins, on soil behaviour and stabilizing mechanisms are not well understood. Thus, the aim of this paper is to characterize the modification of the mechanical behaviour and microstructure of two soils after treatment with one of those product, a vinyl based copolymer. After treatment, both materials were compacted up to their maximum dry density. The mechanical behaviour of the materials as a function of the curing conditions, suction and water content was first determined. In a second step, the alteration of the microstructure by the treatment product was assessed. The results showed that the treatment permitted to significantly improve the strength of the tested soils. Moreover, the efficiency of the product increases when the soil is dried. However, the Young modulus is not significantly modified by the treatment. Microstructural reorganization after co-polymer addition has been detected by SEM technique for kaolin samples, whereas no modification have been observed for silt samples. © The Authors, published by EDP Sciences 2020., Horizon 2020 Framework Programme, H2020 H2020 Marie Sk?odowska-Curie Actions, MSCA: 778120, The project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 778120.

The topic of this study is the archaeometric characterization of mortars from Villa del Pezzolo, a Roman Villa located in Seiano (Napoli-Campania, Italy), dated between the 1st century B.C. and the 3rd century A.D. Mortars were analyzed by means of a multi-analytical approach (polarized optical microscopy, X-ray powder diffraction, scanning electron microscopy and energy-dispersed spectrometry, thermal analyses and mercury intrusion porosimetry) according to existing recommendations. Analytical results evidenced the use of local geomaterials composed of sedimentary and volcanic aggregates in the mix design and confirmed the three distinct building phases identified by archaeologists. Volcanic tuff fragments, identified in the 1st building phase can be ascribed to Campanian Ignimbrite formation, widely cropping out in the Sorrento Peninsula, as confirmed by the presence of glassy shards, partially devitrified and replaced by authigenic feldspar, a typical feature of welded grey ignimbrite lithofacies (WGI). Volcanic aggregates in samples of the 2nd and 3rd building phases show, instead, the presence of leucite-bearing volcanic scoriae and garnet crystal fragments related to Somma-Vesuvius products. Study of these mortars allowed us to: (1) understand the production technologies, (2) highlight use of materials with hydraulic behavior, such as volcanic and fictile fragments, (3) confirm the three building phases from compositional features of mortars and (4) highlight the change over time of the volcanic aggregate for mortars mix-design.

There is a growing concern on lightweight aggregates (LWA) for recycling of waste materials: this manufacturing technology is considered a flexible tool to make it possible the conversion of large amounts of residues into building products. The main challenge for this purpose is the control on the technological behavior during firing of waste-bearing batches. The target is engineering the sintering and expansion of LWA in order to tailor bulk density, mechanical strength and water absorption on various possible applications (e.g., structural and non-structural lightweight concretes, lightweight mortars, filtration substrates, floriculture). The prediction of the aggregate expansion - and hence the batch design - is usually carried out utilizing the Riley's and/or Cougny's schemes, which are based on the bulk chemical composition of clay bodies. However, collecting the literature data on waste-based LWA and plotting them in the Riley's and Cougny's diagrams, no reliable discrimination turns out between expanding and non-expanding batches. In the same way, the attempt to modify the Riley's and Cougny's parameters, including elements present in wastes but not in natural raw materials, was unsuccessful. From this standpoint, a new approach to assess the batch expandability was developed through a deeper comprehension of mechanisms acting on sintering and expansion of LWA. A specific characterization protocol was set up, entailing hot-stage microscopy and determination of phase composition and microstructure. This implies a paradigm shift from batch (chemical composition) to vitreous phase (amount, chemical composition, and viscosity at high temperature). The vitreous phase plays a key-role for bloating, microstructure and physical properties of LWA. A working example is presented about new LWA based on waste glasses, ceramic tile polishing sludge and clay raw materials. (C) 2016 Elsevier Ltd. All rights reserved.

The constant increase in consumption of aggregates for concrete production represents a major environmental issue in the construction industry. Recycled wastes might be used as raw materials in the manufacturing of artificial LightWeight Aggregates (LWAs) in substitution and/or in combination with aggregates produced using natural sources for several end-uses, thus saving non-renewable resources. In this study, a Life Cycle Assessment (LCA) is performed for different LWAs manufactured with raw materials supplied by nature or waste. Then, the LCA is conducted on different concretes made of the different LWAs. (C) 2016 Elsevier Ltd. All rights reserved.

Porosity plays a decisive role in decay processes of stones, as the pore network allows the water penetration responsible for the several physical and chemical deterioration processes affecting stone materials. In this paper two stones (with porosity from high to medium) used in Naples and Vicenza architectures have been considered to investigate the effects produced by the application of an ethyl silicate consolidant and an anti-swelling protective agent on pore space and therefore on stone durability. A deep characterization of the pore system has been carried out as considered crucial to evaluate the effectiveness of conservation treatments and their performance through time. To this purpose, petrophysical and physico-mechanical measurements have been carried out before and after aging tests, on both untreated and treated stones. Conservation treatments, strongly affecting pore size distribution and the behavior towards water absorption, do not always improve the durability of stone, especially in Neapolitan Yellow Tuff (herafter NYT) where a set of meso-macropores was totally annealed as well as a relevant portion of ultramacropores. Such treatments favor the persistence of water in NYT rock structure still after a long time, further contributing to a fast decay of this stone after aging tests. By contrast, treatments in Vicenza Stone (hereafter VS) prevailingly occlude micro- and mesopores and only slightly affect larger pores thus again favoring the flow rate during water desorption test. Moreover, the increase of the average pore radii after treatments also improves the features of this stone that accounts for almost negligible effects after accelerated aging tests.

Industrial minerals represent an important resource for the Italian economy, both in terms of exploitation and transformation, especially in those sectors for which Italy holds a leadership such as ceramics and glass. Among Italian regions Campania is one of the poorest of such kind of resources although some geological formations could be advantageously exploited. An important role is played by the deposits of sedimentary zeolites linked to the activity of different volcanic districts occurring on the Neapolitan territory such as the Campanian Ignimbrite, the most important volcanic episode of the Campi Flegrei (Southern Italy), which blankets a wide area of the Campanian region. The Campanian Ignimbrite has been thoroughly investigated from a volcanological and petrographic point of view. However, little attention was devoted to the attainment of those information useful to verify the potential of the deposit as well as the interpretation of post-depositional mineral-forming processes that have affected this deposit and have led to the formation of several facies, among which the most important are characterized by intense feldspathization (grey facies) and remarkable zeolitization (yellow facies). X-ray diffraction, X-ray fluorescence, inductively coupled plasma emission spectrometry and scanning electron microscopy methods were used to thoroughly characterize the entire set of samples collected from 31 outcrops. Data so far acquired enabled to define the role played by several parameters (i.e., temperature, alkaline and alkaline-earth cations, etc.) in influencing the zeolitization process and the consequent crystallization of phillipsite, chabazite, and analcime. Feldspathization appears to have been controlled mainly by the emplacement temperature of the deposits. The proposed genetic model involves emplacement of the pyroclastic flow in a single episode, producing a deposit with an upward-decreasing temperature gradient. In this model, the central portion had a temperature insufficient to cause significant feldspathization, and the upper portion of the formation was affected by water percolation while still hot, producing progressive zeolitization. Volcano-stratigraphical parameters suggest some constrains on the maximum temperatures affecting the central portion of WGI. Thermodynamic data on zeolites constrain the maximum temperatures of the LYT unit which likely decrease upwards in the unit up to ambient conditions in CPF.

Three Italian zeolitized volcanoclastic deposits with predominant phillipsite, chabazite or clinoptilolite were selected to investigate their attitude to form ceramized products of the Cs- and Sr-enriched forms and to evaluate the effectiveness of immobilization by means of leaching tests. The mineralogical evolution was carefully followed after thermal treatments at increasing temperatures (800 °C up to 1100 °C) which led to the crystallization of prevailing pollucite for Cs-exchanged phillipsite and chabazite and of a Sr-feldspar (about 35 wt.%) along with cristobalite and amorphous matter for all Sr-exchanged zeolites. Cs-enriched clinoptilolite at the same temperature was almost totally amorphous. Leaching tests confirm the substantial immobilization of the polluting cations in the ceramized materials with slight higher values only for the Cs-enriched clinoptilolite, mostly amorphous. Finally, calorimetric tests account for a hydrolysis process widely decreasing after thermal treatments at 1100 °C for phillipsite and chabazite, both Cs- and Sr-enriched, substantially similar for Sr-enriched clinoptilolite and definitely increased in the prevailing amorphous Cs-enriched clinoptilolite. © 2011 Elsevier B.V. All rights reserved.

This research provides possible opportunities in the reuse of waste and particularly muds, coming from both ornamental stone (granite sludges from sawing and polishing operations) and ceramic production (porcelain stoneware tile polishing sludge), for the manufacture of lightweight aggregates. Lab simulation of the manufacturing cycle was performed by pelletizing and firing the waste mixes in a rotative furnace up to 1300 degrees C, and determining composition and physicomechanical properties of lightweight aggregates. The best formulation was used to produce and test lightweight structural concretes according to standard procedures. Both granite and porcelain stoneware polishing sludges exhibit a suitable firing behavior due to the occurrence of SiC (an abrasive component) which, by decomposing at high temperature with gas release, acts as a bloating promoter, resulting in aggregates with particle density1 Mg/m3. However, slight variations of mixture composition produce aggregates with rather different properties, going from values close to those of typical commercial expanded clays (particle density 0.68 Mg/m3; strength of particle 1.2 MPa) to products with high mechanical features (particle density 1.25 Mg/m3; strength of particle 6.9 MPa). The best formulation (50 wt.% porcelain stoneware polishing sludge +50 wt.% granite sawing sludge) was used to successfully manufacture lightweight structural concretes with suitable properties (compressive strength 28 days20 MPa, bulk density 1.4-2.0 Mg/m3).