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This work was funded by the Leverhulme Trust (RPG-2015-071). Dr. C. Cousins also wishes to acknowledge funding from the Royal Society of Edinburgh. This work was financed by FEDER - Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 - Operacional Programme for Competitiveness and Internationalisation (POCI), and by Portuguese funds through FCT - Fundação para a Ciência e a Tecnologia in the framework of the project POCI-01-0145-FEDER-029932 (PTDC/FIS-AST/29932/2017). Exogenous organic molecules are delivered to the surface of Mars annually, yet their fate is largely unknown. Likewise, the survivability of putative organic biomarkers directly implicates current Mars surface exploration ambitions. Among these, amino acids are valuable target molecules due to their abiogenic and biological origins. We present the fundamental, but not previously considered, factors that affect the fate of amino acids embedded in Mars mineral analogues when exposed to ionising radiation. Using existing experimental datasets, we show that the attenuation coefficient at 200 nm for amino acids is an effective parameter for quantifying organic survivability, especially when mineral shielding is limited or absent. Conversely, the dielectric constant of a material is a potential key parameter regarding mineral shielding, as it accounts for iron content, and the physical properties of the material (pore size, surface area or water content). Finally, we combine Martian climatic parameters (surface temperature and atmospheric opacity) to show that the relative UV environment varies significantly on Mars as a function of latitude, providing a reference point for future Mars simulation studies. Postprint

One of the aims of Goal 11 of the UN’s 2030 Agenda for Sustainable Development is to make human settlements sustainable. Some effort should therefore focus on developing maintenance strategies for buildings. Polished granite cladding tiles are very popular for use as flooring material in private and public buildings. These tiles are often treated by mechanical cleaning with detergents and scrubbers, and anionic detergents without chelating agents are usually used to prevent damaging the material. In this study, the anionic detergent Teepol® was applied to granite tiles in order to determine the effect of the treatment on the surface properties of this stone, i.e. appearance, colour, gloss, roughness and hydrophobicity. The results obtained were explained by scanning electron microscopy observations, which enabled characterisation of the microtexture of the surfaces, chemical contamination and any damage to the different granite-forming minerals. The results were compared with those obtained for tiles cleaned by the same mechanical procedure but with tap water in place of detergent and for tiles treated by immersion in water without any mechanical action. In summary, the properties evaluated were affected by the extraction of the typical oxyhydroxylated iron forms that fill cracks in the granite and by the formation of new cracks due to the mechanical action. Moreover, colour changes and the chemical contamination (C-rich deposits with Na, S, Cl, Ca and Mg) hindered the effectiveness of the cleaning procedure.

The on-board identification of ore minerals during a cruise is often postponed until long after the cruise is over. During the M127 cruise, 21 cores with deep-seafloor sediments were recovered in the Trans-Atlantic Geotraverse (TAG) field along the Mid Atlantic Ridge (MAR). Sediments were analyzed on-board for physicochemical properties such as lightness (L*), pH and Eh. Selected samples were studied for mineral composition by X-ray powder diffraction (XRD). Based on XRD data, sediment samples were separated into high-, low- and non-carbonated. Removal of carbonates is a common technique in mineralogical studies in which HCl is used as the extraction agent. In the present study, sequential extraction was performed with sodium acetate buffer (pH 5.0) to remove carbonates. The ratio between the highest calcite XRD reflection in the original samples (Iorig) vs its XRD-reflection in samples after their treatment with the buffer (Itreat) was used as a quantitative parameter of calcite removal, as well as to identify minor minerals in carbonated samples (when Iorig/Itreat &gt, 24). It was found that the lightness parameter (L*) showed a positive correlation with calcite XRD reflection in selected TAG samples, and this could be applied to the preliminary on-board determination of extraction steps with acetate buffer (pH 5.0) in carbonated sediment samples. The most abundant minerals detected in carbonated samples were quartz and Al- and Fe-rich clays. Other silicates were also detected (e.g., calcic plagioclase, montmorillonite, nontronite). In non-carbonated samples, Fe oxides and hydroxides (goethite and hematite, respectively) were detected. Pyrite was the dominant hydrothermal mineral and Cu sulfides (chalcopyrite, covellite) and hydrothermal Mn oxides (birnessite and todorokite) were mineral phases identified in few samples, whereas paratacamite was detected in the top 20 cm of the core. The present study demonstrates that portable XRD analysis makes it possible to characterize mineralogy at cored sites, in particular in both low- and high-carbonated samples, before the end of most cruises, thus enabling the quick modification of exploration strategies in light of new information as it becomes available in near-real time.

The archaeological site of Almaraz is located in the old part of the city of Almada, in the south shore of Tagus River, region of Lisbon. The excavated findings and the radiocarbon dating of the contexts where these were found show an occupation that can in fact be dated from the 8th to the 7th c. BCE period, thus a very early stage of the Phoenician occupation in the Iberian Peninsula. Numerous amphorae sherds were found at Almaraz. A spectroscopic characterization of those ceramics was made and is presented here, to help us understand if they were produced locally, in Lisbon workshops, or imported. Sixteen sherds representative of the thousands found at Almaraz were studied with the use of non-invasive spectroscopies, namely by crossing information from micro-Raman and X-ray fluorescence emission data. X-ray diffraction experiments were also performed. In spite of the fact that no ceramic kilns were found at Almaraz until now, the results point to two major groups of amphorae of local origin: one which used clays of Miocene origin, found on the southern shores of the Tagus River, very close to the Almaraz site, at Palenca (with quartz, anorthite, diopside and hematite). Another group, remarkably different, made use of clays of Pliocene origin also from the Tagus Estuary, the Fontainhas clay source (where quartz, anorthite, muscovite and hematite were found).

22 páginas.-- 6 figuras.-- 115 referencias.-- Additional Supporting Information may be found in the online version of this article: http://dx.doi.org/10.1111/sed.12431, Subsurface granitic environments are scarce and poorly investigated. A multi‐disciplinary approach was used to characterize the abundant moonmilk deposits and associated microbial communities coating the granite walls of the 16th Century Paranhos spring water tunnel in Porto city (north‐west Portugal). It is possible that this study is the first record of moonmilk in an urban subsurface granitic environment. The morphology and texture, mineralogical composition, stable isotope composition and microbial diversity of moonmilk deposits have been studied to infer the processes of moonmilk formation. These whitish secondary mineral deposits are composed of very fine needle‐fibre calcite crystals with different morphologies and density. Calcified filaments of fungal hyphae or bacteria were distinguished by field emission scanning electron microscopy. Stable isotope analysis revealed a meteoric origin of the needle‐fibre calcite, with an important contribution of atmospheric CO2, soil respiration and urn:x-wiley:00370746:media:sed12431:sed12431-math-0001 from weathering of Ca‐bearing minerals. The DNA‐based analyses revealed the presence of micro‐organisms related to urban contamination, including Actinobacteria, mainly represented by Pseudonocardia hispaniensis, Thaumarchaeota and Ascomycota, dominated by Cladosporium. This microbial composition is consistent with groundwater pollution and contamination sources of the overlying urban area, including garages, petrol stations and wastewater pipeline leakage, showing that the Paranhos tunnel is greatly perturbed by anthropogenic activities. Whether the identified micro‐organisms are involved in the formation of the needle‐fibre calcite or not is difficult to demonstrate, but this study evidenced both abiotic and biogenic genesis for the calcite moonmilk in this subsurface granitic environment., The authors acknowledge the Spanish Ministry of Economy, Industry and Competitiveness (MINEICO, project CGL2011-2569) and the Portuguese Foundation for Science and Technology, FCT (UID/GEO/04035/2013, UID/ECI/04028/2013, PEst-OE/CTE/UI0098/2011) and the LABCARGA| ISEP re-equipment program (IPP-ISEP|PAD’2007/ 08) for financial support. AZM thanks MINEICO for the ‘Juan de la Cierva – Incorporación’ postdoctoral contract (IJCI-2014-20443). PMMS thanks the Spanish Ministry of Science and Innovation for his contract associated with the ‘Research Programme in Technologies for the Assessment and Conservation of Cultural Heritage’ (TCP CSD2007-0005

The recovery of lithium from hard rock minerals has received increased attention given the high demand for this element. Therefore, this study optimized an innovative process, which does not require a high-temperature calcination step, for lithium extraction from lepidolite. Mechanical activation and acid digestion were suggested as crucial process parameters, and experimental design and response-surface methodology were applied to model and optimize the proposed lithium extraction process. The promoting effect of amorphization and the formation of lithium sulfate hydrate on lithium extraction yield were assessed. Several factor combinations led to extraction yields that exceeded 90%, indicating that the proposed process is an effective approach for lithium recovery. info:eu-repo/semantics/publishedVersion

Black crusts on different substrates (carbonate and silicate stones, cement-based mortar and carbonate detrital deposits) in urban environments were characterized microscopically by analysing their morphologies and compositions. The objective of this article is to study the interaction between the substrate and the crust and the influence of the environmental conditions on the crust development. On the one hand, the internal structure and morphology of each sample were evaluated with stereo and scanning electron microscopies. On the other hand, the black crust composition was accessed by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy in backscattered electron mode combined with energy dispersive x-ray spectroscopy. The results of these analytical techniques provided interesting information about the composition and the mineralogical phases present in the collected black crusts. In most of the cases, gypsum was detected as the main component exhibiting different habits. Calcite was also detected in all the evaluated gypsum black crusts; its presence was attributed to different origins. The substrate-crust interaction was also evaluated, contributing to distinguish different crust development processes in relation to the substrate. In carbonate substrates (limestones, mortar and carbonate detrital deposits), it was detected a continuous diffuse boundary related to the replacement of Ca-carbonate by Ca-sulphate, while this boundary was significantly more defined for the granitic stone. This study shows that the substrate, the presence of different construction materials, (e.g. mortars), the motor exhaust particulate substances and the concentrations of atmospheric pollutants, the marine influence as well as biological or other anthropogenic compounds are decisive factors in the development of the black crust. Some ideas about the establishment of conservation strategies are also shown.

11 páginas.- 7 figuras.- 1 tabla.- 73 referencias.- Supplementary data to this article can be found online a https://doi.org/10.1016/j.scitotenv.2019.134321, Siliceous speleothems frequently reported in volcanic caves have been traditionally interpreted as resulting from basalt weathering combined with the activity of microbial communities. A characteristic feature in lava tubes from Hawaii, Azores and Canary Islands is the occurrence of black jelly-like speleothems. Here we describe the formation process of siliceous black speleothems found in a lava tube from La Palma, Canary Islands, Spain, based on mineralogy, microscopy, light stable isotopes, analytical pyrolysis, NMR spectroscopy and chemometric analyses. The data indicate that the black speleothems are composed of a hydrated gel matrix of amorphous aluminum silicate materials containing charred vegetation and thermally degraded resins from pines or triterpenoids from Erica arborea, characteristic of the overlying laurel forest. This is the first observation of a connection between fire and speleothem chemistry from volcanic caves. We conclude that wildfires and organic matter from the surface area overlying caves may play an important role in the formation of speleothems found in La Palma and demonstrate that siliceous speleothems are potential archives for past fires., A.Z. Miller acknowledges the support from the Marie Curie Intra-European Fellowship of the European Commission seventh Framework Fig. 6. Contour van Krevelen density plots displaying cumulative abundances of pyrolysis compounds identified in Table S2 for: A) Erica arboreabiomass, B) Andosol topsoil, C) Black jelly-like speleothem 1 (BS1), and D) Black jelly-like speleothem 2 (BS2).9A.Z. Miller et al. / Science of the Total Environment 698 (2020) 134321 Programme (grant PIEF-GA-2012-328689) and the CEECIND/01147/2017 contract funded by Fundação para a Ciência e a Tecnologia (Portugal). The authors acknowledge the Spanish Ministry of Economy and Competitiveness (project CGL2013-41674-P) and ERDF funds forfi-nancial support. The authors are grateful to the speleologist OctavioFernández (GE Tebexcorade–La Palma) for the assistance during thefield trip and photographic documentation in the lava tubes from LaPalma Island

Calcium diglyceroxide (CaD) was used as the catalyst for biodiesel production through oil methanolysis. It was evaluated its catalytic behavior, its air expo- sure tolerance, and the Ca leaching. CaD catalyst was synthesized from food waste scallop shell derived CaO (obtained by calcination at 900 °C) by contacting with a mixture of equal volumes of glycerin and methanol at 65 °C for 2 h. The CaO obtained by calcination of scallop shell was used as reference catalyst. In standard reaction conditions (2.5 h, methanol reflux temperature, 5 wt% (oil basis) catalyst loading, and methanol:oil = 12:1 moral ratio), CaD presented lower catalytic activity than CaO (FAME yield of 92% against 99%, respectively). 24 h repined CaD presented improved catalytic behavior probably due to the formation of surface Ca −OH groups, achieving 96% of FAME yield. Thermogravimetry (TG) data showed that inorganic residue was larger for biodiesel than for glycerin, being CaD catalyst more soluble than CaO. Data showed that CaD is unstable under reaction conditions, suffering leaching, but the absence of Matter Organic Non-Glycerol (MONG) in the glycerin phase allows to neglect the homogeneous contribution of the leached catalyst. CaD formation during reaction contributes to FAME contamination with Ca and promotes catalyst deactivation thus being an undesired occurrence.

São Domingos sulfide mine was shut down more than 50 years ago leaving behind eroded and depositional surfaces due to acid mine drainage (AMD). The aim of this study was to assess six selected sites subjected to AMD, considered phytotoxic regions characterized by vegetation scarcity. Two main criteria, nature and composition of soluble fractions and total chemistry of surficial products related to jarosites presence, enabled to set up an overall dichotomy between superficial proximal/discharge and distal/sedimentation areas. Wet and dry sieving results comparison revealed that samples have a predominant sandy texture and lithic (phyllite, quartzite and volcanic country rocks) composition. Quartz, and subordinate feldspar enrichment is also detected in the coarse silt fraction. The results also suggest that the materials under study, when subjected to the local torrential hydrologic regime, have a high mechanical vulnerability, facilitating erosion and mud transport, both critical for vegetation support, and triggering contamination transfer and dispersion. The vicinity and ground-level surfaces of discharging areas are enriched in the jarosite group minerals whereas the sedimentation ones present hypersaline aluminous tendency. The formation of jarosite is considered as an efficient positive environmental contribution to metals and metalloids sequestration/immobilization. The remediation/revegetation solutions to be adopted in each location must have into consideration these differentiating aspects.

Stone coatings, biological colonization, efflorescence and detachments are frequent on granitic surfaces of our cultural heritage infrastructure. In order to find the different origins for each deterioration form, this paper studies and compares several coatings, efflorescence and flakes found on granitic surfaces of bridges from different ages built in the same area (Ourense in NW Iberian Peninsula at 90 km from the sea) under the same environmental and traffic conditions. The most recent bridge was the New Bridge built in the beginning of 20th century and the oldest one was the Roman Bridge with the 1st century AD foundations but its current structure was built in 17th century. The New Bridge has exhibited a greater variety of deterioration forms such as black crusts, carbonate crusts, efflorescence and biological colonization. On the Roman Bridge, black crusts, efflorescence to a greater extent, and flakes associated with salt crystallization processes have been identified. Scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray diffraction and Fourier transform infrared (FTIR) spectroscopy studies were carried out in order to establish their composition, and optical and electronic microscopies and X-ray microtomography were used to study their morphologies. As a result, anthropogenic factors (industrial activities, traffic pollution and fertilizers) are considered to be the main contributors to crusts, efflorescence and flake formation on both studied substrates (granite ashlars and mortars). To a lesser extent, natural factors (marine influence and bird droppings) should be taken into account.

The main factors that affect the extraction of metals from spent lithium-ion batteries by acid leaching using H2SO4, and sodium metabisulphite, were evaluated and optimized through a set of experiments, framed by a techno-economic approach. The maximum value of the profit response was obtained with the highest possible values of acid concentration (2.5 M) and time (2 h), a liquid/solid ratio of 5 L/kg, and the lowest possible value of temperature (40 degrees C). After leaching, the electrodes active material contained in the metals decreased, while it was still significant in the graphite, as observed by scanning electron microscopy-energy dispersive spectrometry and x-ray powder diffraction. Even though the performed economic evaluation was a summarized outline it can be considered suitable to compare different leaching conditions and to determine the possible best combinations of factors that can optimize the profit response. info:eu-repo/semantics/publishedVersion

The hydrometallurgical extraction of metals from spent lithium-ion batteries (LIBs) was investigated. LIBs were first dismantled and a fraction rich in the active material was obtained by physical separation, containing 95% of the initial electrode, 2% of the initial steel and 22% of plastic materials. Several reducers were tested to improve metals dissolution in the leaching step using sulphuric acid. Sodium metabisulphite led to the best results and was studied in more detail. The best concentration of Na2S2O5 was 0.1 M. The metals dissolution increased with acid concentration, however, concentrations higher than 1.25 M are unnecessary. Best results were reached using a stirring speed of 400 min(-1). The metals leaching efficiency from the active material (Li, Mn, Ni, Co) increased with the temperature and was above 80% for temperatures higher than 60 degrees C. The dissolution of metals also rose with the increase in the liquid/solid ratio (LAS), however, extractions above 85% can be reached at LAS as lower as 4.5 L/kg, which is favourable for further purification and recovery operations. About 90% of metals extraction can be achieved after only 0.5 h of leaching. Sodium metabisulphite can be an alternative reducer to increase the leaching of Li, Mn, Co, and Ni from spent LIBs. info:eu-repo/semantics/publishedVersion

9 páginas.-- 3 figuras.-- 2 tablas.-- 83 referencias.-- Selected paper from the XVI Latin-American Congress on Chromatography (XVICOLACRO) and the 9th National Meeting on Chromatography (9ENC), 5–9 January 2016, Lisbon, Portugal., This study comprises an innovative approach based on the combination of chromatography (analytical pyrolysis and pyrolysis compound-specific isotope analysis (Py-CSIA)), light stable isotopes, microscopy and mineralogy analyses to characterize the internal layering of coralloid speleothems from the Ana Heva lava tube in Easter Island (Chile). This multidisciplinary proxy showed that the speleothems consist of banded siliceous materials of low crystallinity with different mineralogical compositions and a significant contribution of organic carbon. Opal-A constitutes the outermost grey layer of the coralloids, whereas calcite and amorphous Mg hydrate silicate are the major components of the inner whitish and honey-brown layers, respectively. The differences found in the mineralogical, elemental, molecular and isotopic composition of these distinct coloured layers are related to environmental changes during speleothem development. Stable isotopes and analytical pyrolysis suggested alterations in the water regime, pointing to wetter conditions during the formation of the Ca-rich layer and a possible increase in the amount of water dripping into the cave. The trend observed for δN values suggested an increase in the average temperature over time, which is consistent with the so-called climate warming during the Holocene. The pyrolysis compound-specific isotope analysis of each speleothem layer showed a similar trend with the bulk δC values pointing to the appropriateness of direct Py-CSIA in paleoenvironmental studies. The δC values for n-alkanes reinforced the occurrence of a drastic environmental change, indicating that the outermost Opal layer was developed under drier and more arid environmental conditions., A.Z. Miller acknowledges the support from the Marie Curie Intra-European Fellowship of the European Commission’s 7th Framework Programme (PIEF-GA-2012-328689). The Spanish Ministry of Economy and Competitiveness (MINECO, project CGL2013-41674-P) and the FEDER Funds are acknowledged for the financial support. N.T. Jiménez-Morillo thanks the MINECO for funding his pre-doctoral FPI fellowship (BES-2013-062573).

11 páginas.-- 8 figuras.-- 1 tabla.-- 33 referencias, Coralloid-type speleothems were recorded on the ceiling of the Ana Heva lava tube in Easter Island (Chile). These speleothems were morphologically, geochemically and mineralogically characterized using a wide variety of microscopy and analytical techniques. They consist dominantly of amorphous Mg silicate and opal-A. Field emission scanning electron microscopy revealed a variety of filamentous and bacillary bacteria on the surface of the Ana Heva coralloid speleothems, including silicified filamentous microorganisms. Among them, intriguing reticulated filaments resemble those filaments documented earlier in limestone caves and lava tubes. The identification of silicified microorganisms on the coralloid speleothems from the Ana Heva lava tube suggests a possible role of these microorganisms in silica deposition. © 2014 Copyright Taylor and Francis Group, LLC., This research was partially financed by Portuguese Funds through FCT- Fundaçao para a Ciencia e a Tecnologia (PEst-OE/CTE/UI0098/2011) and also by the Spanish Ministry of Science and Innovation (Project CGL2011–2569). This work was supported by FCT grant to AZM (SFRH/BPD/63836/2009).

The aim of this study is to apply X-ray microfocus computed microtomography (μ-XCT), a promising non-destructive 3D microscopy imaging technique, based on measurements of X-ray linear path attenuation coefficient, in order to study a Portuguese travertine, a random heterogeneous geomaterial used in urban heritage constructions. This study evaluates the impact of soluble sulphate salt–induced decay phenomena on texture characteristics at a micrometric scale. This is done to better describing, imaging, measuring and understanding the impact of an artificially induced sulphate-decay process on petrographic/petrophysical properties. A Portuguese travertine was chosen as the object of our study. Its laboratory-induced changes were systematically monitored, using non-destructive techniques, to determine voids (pores + fractures)/matrix fractions and size spectrum evolution based on 3-D images. This investigation demonstrates that the μ-XCT potential constitutes a valid complementary tool when analysing decay processes of complex natural materials in different environmental conditions. It clearly provides suggestive and important qualitative and/or quantitative estimates, at different spatial scales, of environmentally induced stone voids/matrix network spatial structure-texture evolution correlations. Further qualitative/quantitative parameterization assessment and statistical validation will be the next step to be taken on this study., Fundação para a Ciência e a Tecnologia (FCT) através do projeto POCTI\CTA\44940\2002_PORENET e os projetos estratégicos PEstOE/CTE/UI0697/2011 and PEst-OE/CTE/UI0098/2011 (fundos nacionais e europeus - FEDER)