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Natural resources, along with critical raw materials, are increasingly considered a focus for technological applications. Widely available and inexpensive natural resources, such as zeolite-rich geomaterials, possess minero-chemical characteristics that make them very useful in various technological applications, representing a strategic choice with a strong green connotation. In this research, the possibility of recycling waste powders from quarrying operations of zeolite-rich tuffs in technological applications for the construction sector and drug delivery was investigated. Waste powders collected from quarries operating on the Sorano Formation (Tuscany - Italy), were used for a preliminary characterization, performed to evaluate zeolite content and potential pollution deriving from industrial processing. Thereafter, the specific technological characterization was carried out to define the waste attitude to represent a promising candidate raw material for Lightweight Expanded Aggregates (LEA) production, partial substitution component with pozzolanic activity in cement formulations, carrier for active pharmaceutical molecules. Experimental results, obtained following European normative, proved that was possible to produce waste-based LEA with comparable features with those reported for currently marketed products, that waste powders exhibited pozzolanic activity evidencing the possible use as addition for blended cements and, finally, the use of a cationic surfactant determined a surface-modification of natural zeolites (contained in waste samples) which encouraged for an early loading trial of active pharmaceutical molecules. This research can be safely extended to other quarry waste, with similar mineralogical and chemical composition, leading to a strong contribution in the waste management of this sector. • The Sorano Formation is quarried and processed with a huge production of waste mainly composed of zeolites. • Zeolite-rich waste is suitable for production of lightweight aggregates meeting technical requirements for building sector. • Zeolite-rich waste can be considered as a partial substitutefor cement additions due to the pozzolanic activity index. • Functionalisation of the zeolites from the Sorano formation waste enables the loading of pharmaceutically active molecules. [ABSTRACT FROM AUTHOR]

Roman mortars from a mausoleum (named D46b) belonging to the archaeological site of Porta Mediana necropolis, in Cuma (Naples, Southern Italy) have been studied by means of petrographic, mineralogical and micro-chemical analyses. The aim of this research is to fill the knowledge gap regarding mortar-based materials used in Roman age within this wide archaeological site. Two typologies of mortars (bedding and coating) were collected from mausoleum's masonry. They were lime-based with addition of pozzolanic materials, according to Vitruvius' recipe. Raw materials, such as volcanic sand and limestones, mainly from local sources, were preferentially used as aggregate, both for great availability and good properties. As regard production techniques, the multi-layer feature of the coating mortars, once again shows the great knowledge of the building art. Each layer is the result of a precise choice, as shown by the differences both in texture and petrographic features. Data from detailed mortars characterization have infer the outstanding skill of Roman craftsmen, as already proved by extraordinary durability of buildings. The research was very useful not only to increase the knowledge of this ancient culture but also to planning conservative actions, that, through mortar reproduction or the research of suitable materials, can promote the safeguard of this invaluable heritage. [ABSTRACT FROM AUTHOR]

This research aims to deepen knowledge on geomaterials used in building operations of a very important monumental complex belonging to the "Porta Mediana" necropolis the archeological site of Cuma. The entire site counts 70 mausoleums among which, the one named "Sphinx complex" or A63, is particularly important. For its realization several geomaterials have been used. Analytical results were carried out from several techniques such as optical microscopy, microchemical and mineralogical-petrographical analysis, scanning electron microscopy with EDS and X-ray powder diffraction. This approach allows to clarify the provenance of natural geomaterials and also the technological processes involved in the production of artificial geomaterials (mortars, plasters, cocciopesto). Phlegrean tuffs, due to their easy workability and good mechanical features, were used mainly for masonries and for decorative function (a bas-relief of a "sphinx" for example). As far as artificial geomaterials are concerned, the use of a volcanic aggregate, was privileged too. Some examples of imported stones were also found: limestones and marbles, the first one implemented as a building material for cippi of the fence while the second one for prestigious coating elements. Results permitted to evaluate building techniques of the period and mainly the wide potential of Phlegrean fields' materials when used as a bulding stone. This research aims also to give important informations for restoring and conservative actions useful for mausoleums of the entire site. [ABSTRACT FROM AUTHOR]

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. • Old screens and ceramic muds show to be suitable for lightweight aggregates production. • Waste-based lightweight aggregates production and characterization. • Use of waste-based lightweight aggregates in concrete manufacturing. • Characterization of concrete containing waste-based coarse aggregates. • Comparison between experimental products (aggregates and concretes) and commercial ones. [ABSTRACT FROM AUTHOR]

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 °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 exhibits suitable tiring 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 density <1 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 days >20 MPa, bulk density 1.4-2.0 Mg/m³). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This study aimed to examine the impact of different surface properties of poly(lactic-co-glycolic) acid (PLGA) nanoparticles (P NPs) and PLGA-Poloxamer nanoparticles (PP NPs) on their in vivo biodistribution. For this purpose, NPs were formulated via nanoprecipitation and loaded with diphenylhexatriene (DPH), a fluorescent dye. The obtained NPs underwent comprehensive characterization, encompassing their morphology, technological attributes, DPH release rate, and thermodynamic properties. The produced NPs were then administered to wild-type mice via intraperitoneal injection, and, at scheduled time intervals, the animals were euthanized. Blood samples, as well as the liver, lungs, and kidneys, were extracted for histological examination and biodistribution analysis. The findings of this investigation revealed that the presence of poloxamers led to smaller NP sizes and induced partial crystallinity in the NPs. The biodistribution and histological results from in vivo experiments evidenced that both, P and PP NPs, exhibited comparable concentrations in the bloodstream, while P NPs could not be detected in the other organs examined. Conversely, PP NPs were primarily sequestered by the lungs and, to a lesser extent, by the kidneys. Future research endeavors will focus on investigating the behavior of drug-loaded NPs in pathological animal models. [ABSTRACT FROM AUTHOR]

This paper reports a detailed study on some relevant portions of the main façades of Caserta Royal Palace (Reggia di Caserta), one of the most important Italian monuments, comparable for its impressive architecture to the Royal Palace of Versailles in France and considered the largest royal palace in the world by volume. The research was focused on the weathering pathologies affecting the stone surfaces that, in the last decades, suffered several detachments of fragments from the coatings and from other architectural elements such as string courses, eaves, and capitals. A preliminary characterization of the materials of the façades and an evaluation of the relative weathering pathologies provided the information required for appropriate restoration and securing of these portions of the building. In particular, an innovative evaluation procedure which draws on techniques typical of the earth sciences allowed the proposal of a 'risk attitude' applied to discrete portions of the geomaterials used in the built heritage which is based on the influence of different factors leading to weakening of the stone and to the final detachment of rock fragments. Such a large and complete set of information should be carefully considered by the project planners to adopt the required steps for a suitable risk mitigation and for securing the site during restoration. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This research deals with mineralogical, petrographic, chemical, and microstructural characterization of raw materials from the Roman Dragonara cave (Phlegraean Fields, Campania region, Italy) through Polarized Light Microscopy (PLM), X-ray Powder Diffraction (XRPD), Field Emission Scanning Electron Microscopy coupled with an Energy Dispersive Spectrometer (FESEM/EDS), Simultaneous Thermal Analysis (STA) and Mercury Intrusion Porosimetry (MIP). The aim of this study was to asses mortars hydraulic properties along with provenance of raw materials and mortars recipe. A focus on the reactions between the surface of the ceramic aggregates and volcanic materials with binding matrix proved to be crucial to define their role in the mix design of mortars. Representative results showed that hydraulicity of the analyzed mortars is mainly due to volcanic materials rather than ceramic fragments. In fact, reaction active elements such as Reaction Rims (RR), Interfacial Transition Zones (ITZ) and particularly Ca-rich rims were usually found at the matrix-volcanic fragments interface. Moreover, porosity tests evidence that bedding mortars, which contain mainly volcanic material and only sporadically ceramic fragments have a higher closed porosity of binder matrix due to the good pozzolanic reactivity. • Ancient mortars used ceramic fragments as pozzolanic materials. • Mortars hydraulicity due to technological addition. • Role of aggregates in mortars physical characteristics. • Multianalytical approach in historical mortars examination. • Secondary phases improving the technological properties of mortars. [ABSTRACT FROM AUTHOR]

• Historic center of Naples is one of the UNESCO word heritage sites. • Cathedrals, churches and chapels are subject to cavity collapse. • Places of worship are above a connected network of underground cavities. • DInSAR analysis suggest the presence of anomalous areas. • 95 places of worship of the historic center of Naples are susceptible to sinkholes. The historic center of Naples (southern Italy) is characterized by a variety of elements which, forming its cultural asset, have contributed to its recognition as a UNESCO World Heritage site. Among these, cathedrals, churches and chapels are particularly relevant due to their diffusion and differentiation in age. A singular feature of these places of worship is the presence of a frequently connected network of underground cavities. Such cavities, excavated for quarrying tuff blocks, are susceptible to sudden collapses generating sinkholes which in a number of cases have been responsible for the loss of human lives. On this basis and considering the importance of such elements as attractors of visitors, an analysis of susceptibility to sinkholes of cathedrals, churches and chapels has been here carried out. A sinkhole, cavities and places of worship inventory was prepared using available data and was used, in association to ongoing ground deformation data obtained by DInSAR. Results indicated that 40% of the inventoried sinkholes are a product of cavity collapses and in 45 cases cavities lie underneath places of worship. Geodetic data obtained by Differential Interferometric SAR technique indicate that approximately 1 km2 of the historic center of Naples is subject to ongoing subsiding deformation that in several cases is localized above cavities. The susceptibility map derived from available data indicate the presence of a zone where no cathedral, church and chapel can be subject to sinkholes (1) and 3 zones where they can be subject to sagging (2), potential future cavity collapses (3) and future cavity collapses anticipated by ongoing deformation (4); in detail, 34 places of worship are in zone 2, 57 in zone 3 and 9 in zone 4. Considering an increasing susceptibility level of the identified zones, the 9 places of worship located in zone 4 require a quick response in terms of characterization, stability analysis and real time monitoring have been identified. [ABSTRACT FROM AUTHOR]

• Terme di Baia is one of the most important archaeological sites in Southern Italy. • Microstructural and compositional examination of coating mortars. • Long-lasting use of a valuable mix design created with local raw materials. • Secondary phases improved the technological properties of mortars. Ancient pozzolanic mortars show the high technological quality achieved by Roman construction workers, due to their ' excellent state ' of preservation in every environment. These workers well knew that thanks to the combination of lime with specific volcanic products (pozzolana), mortar and concrete become hydraulic, allowing underwater hardening and increasing mechanical strength. The use of pozzolana in a mortar provides the underwater curing (hydraulic limes) of whatever construction with higher speed compared to carbonation processes of slaked lime. Whenever pozzolana is not available, it is substituted by ceramic fragments, which possess similar hydraulic properties. This research focuses, for the first time, on the detailed characterization of mortars coming from the Thermal Complex of Baia, which represents one of the most important archaeological sites in the Campania region. Thanks to several thermal springs, the ancient city of Baiae (Campi Flegrei) was the holiday resort of the Roman aristocracy. The former Soprintendenza Archeologia della Campania , allowed us to perform non-invasive, but representative, sampling of mortars that were characterised by multianalytical methodologies (POM, XRPD, SEM-EDS, TGA, and MIP) providing useful information on possible future activities of restoration. Results confirmed the expertise of Roman workers, who skilfully combined volcanic tuff aggregate, hydrated lime, and ceramic fragments. In particular, the typical zeolitic mineral association of phillipsite > chabazite > analcime found in the tuff aggregate pointed out their provenance from the Neapolitan Yellow Tuff related to the volcanic activity of Campi Flegrei of ca. 15 ka BP. The most relevant characteristic detected in all studied samples is the mortar hydraulicity testified by evidences such as reaction rims between pozzolana and binder, Hydraulicity Index (HI), and thermal analyses investigation. Also, composition of secondary mineralogical phases in the cementiceous matrix is particularly relevant. Distinctive is the contemporary presence of C-A-S-H gel, calcite and gypsum. C-A-S-H gel is derived from lime/ceramic fragments reaction; calcite is likely related to the partial reaction of underburned lime; and gypsum could be ascribable to the sulphation process of calcite. These secondary minerogenetic products fill pore space and enhance bonding in pumice fragments, thus contributing to long-term durability of mortars. [ABSTRACT FROM AUTHOR]

• Complexation of HC with all CDs was more effective in water than in a water:ethanol mixture. • HC-γCD and HC-βCD complexes exhibited a qualitatively different solubility profiles. • Solubility enhancement was the highest with HPβCD. • Potential implications for improving drug delivery systems in ocular inflammatory and autoimmune disorders. Hydrocortisone (HC) is widely utilized in the pharmaceutical field for various administration routes, including oral, parenteral, and topical routes. However, its application in ocular disease treatment as a solution is limited due to its poor aqueous solubility. To address this limitation, in this study we aimed to investigate different types of cyclodextrins (CDs) to identify the most effective CD for improving the inherent solubility of HC. Results from scanning electron microscopy, rheology and differential scanning calorimetry (DSC) demonstrated the formation of inclusion complexes, while isothermal titration calorimetry (ITC) investigations accurately determined the thermodynamic parameters associated with the formation of complexes between HC and HPβCD or βCD, at 25 and 37 °C. Additionally, phase solubility studies in PBS buffer at 37 °C confirmed the formation of stable inclusion complexes. Collectively, results indicated that HPβCD was the most effective CD in enhancing the intrinsic solubility of HCs in PBS highlighting its potential for improving the solubility and formulation of HC-based pharmaceutical products. [ABSTRACT FROM AUTHOR]

This current research is focused on the mineralogical and petrographic characterisation of mortar-based materials from Villa San Marco in the ancient Stabiae (modern Castellammare di Stabia, Napoli), an outstanding example of Roman otium villae , and aims at recognising the technology used by the ancient skilled workers. Several analytical techniques were used such as digital videomicroscopy, optical microscopy, digital image analysis, scanning electron microscopy coupled with EDS analysis and Quantitative Powder X-ray Diffraction. A multi-layer technology characterised the plasters; the scratch coat was made with lime mortars mixed with a pozzolanic lightweight aggregate and cocciopesto , required ingredients providing a quick-setting and a better adhesion with the support. As far as the arriccio layer is concerned, the mix-design is a lime mortar with volcanic sand as the aggregate and a minor content of pozzolan and/or cocciopesto to enhance the workability of the mortar in order to correct any error due to the roughness of the scratch coat. The plaster s.s. was the removable support in case of mistakes, and gave a lighter colour to the preparation layer of the frescoes. The last thin layer, prepared with lime mortars and a carbonate aggregate, is characterised by low porosity in order to avoid pigment adsorption. The painting technique was a fresco with encaustication . In contrast, the mortars of the building structures were made with lime added to a pozzolanic aggregate (volcanics and cocciopesto ), giving a quick setting during the implementation of the yellow tuff opus reticulatum . The rudera and nuclei of the mosaics were built with abundant volcanic sand and cocciopesto mixed with the lime, producing a more resistant surface, and finally the tesserae were fixed exclusively with lime. The white and black colours of the mosaics were produced by local limestone and tephritic lava. The results permitted an evaluation of the high level of specialization of both the workers and the artists that built and decorated these maritime villas. Moreover, the collected data highlighted the wide potentiality of the materials cropping out in the environs of the Somma-Vesuvius volcanic complex. This research aims at furnishing a useful reference for future restoration action in Villa San Marco and the other Roman villas in this area. [ABSTRACT FROM AUTHOR]

Abstract: 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 35wt.%) 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. [Copyright &y& Elsevier]