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This study aims at synthesizing a novel Surface-Enhanced Raman Spectroscopy (SERS) sensor based on a nanostructured substrate, calcium silicate hydrate (C-S-H), the main hydration product of Portland cement. The procedure involves first the incorporation of silver within the nanostructure of the gel (C-S-Ag-H) and second the modification of the surface of pellets of the newly synthesized material by laser irradiation at 532 nm or 355 nm. The assessment of the SERS activity revealed no amplification of the organic molecule rhodamine B (RdB) signal, used as a probe, on the C-S-Ag-H before laser irradiation. However, after laser irradiation, the SERS effect was comparable to that of reference colloidal Ag nanoparticles (NPs). This SERS response is attributed to an increase in the concentration of metallic silver on the surface of the C-S-Ag-H pellets upon laser irradiation and material ablation as revealed by X-ray Photoelectron Spectroscopy (XPS). Further enhancement of the SERS signals was induced by depositing colloidal Ag NPs on the irradiated pellets, giving rise to interparticle hot spots where the electromagnetic field is further intensified.

Early November 1597. After an intense combat with four enemy ships, San Giacomo di Galizia (also known as Santiago), a just over 1000-ton galleon, enters the Ribadeo harbour in a terrible state, where it wrecks. This war vessel had been built in Naples in 1590 and sailed the Mediterranean and the Atlantic until it sank. In late November 2011, during an archaeological survey of the dredge area to improve the navigation of the ports in Galicia, a large ship was found and identified as the San Giacomo, which wrecked 414 years prior to its discovery. Several archaeological campaigns permitted a thorough record of the wreck and the recovery of hundreds of objects which this ship carried on its final journey. These artefacts included ceramics, metalwork, and wood, objects which reflected the activities that occurred on board during its short life. Combining an interdisciplinary approach based on artefacts, documents, and chemical analysis, the aim of this paper is to, on the one hand, attempt to reconstruct the sailing itinerary of the ship over its period of use and, on the other, to discuss how these commodities can help to write new narratives about the activities which occurred on board.

Silanes added during mortar or concrete preparation, may modify the fresh state properties, hydration kinetics and mechanical strength of the final product. The effects of silanes on cement hydration have been widely studied in the literature, however, there is some controversy about its effect at short ages. The present study was undertaken to determine the effect of a TEOS-based alkoxysilane (UCA-T), produced by ultrasound-assisted pre-hydrolysis of an oligomeric precursor, on early age cement paste hydration. The nature of the processes modifying the various stages of cement hydration kinetics in the presence of the alkoxysilane was ascertained by analysing paste composition at several ages (defined on the grounds of calorimetric curve results) using XRD, TG-DTG, FTIR and Raman spectroscopy. The calorimetric curve of pastes containing UCA-T exhibited a new early age, pre-induction period exothermal peak, indicative of UCA-T hydrolysis, C3A and C3S dissolution and ettringite and C–S–H gel precipitation. Portlandite, however, did not precipitate but reacts with the Si(OH)4 sourced from UCA-T hydrolysis to generate further C–S–H gel. The induction period following on that new exothermal peak was considerably longer than the period observed in the reference cement, an effect that intensified at higher UCA-T content.

This is the experimental dataset used in the paper Eur. Phys. Plus, 136:859 (2021) (http://hdl.handle.net/10261/248668). Historical glass-based objects undergo, since the time of their manufacture, different degradation phenomena that are related to their composition and to the environment to which they were exposed. Three-dimensional (3D) structural and chemical characterization of the degradation layers is important to select the most adequate conservation strategies for glass objects. Optical microscopy (OM) is the most frequently used non-destructive method to examine the surface of historical glasses; however, the 3D structural assessment of alteration layers requires applying the destructive modality of this technique to conduct a cross-sectional study. In this work, a different approach for structural and compositional characterization of alteration layers on model medieval-like glasses is presented, based on the combination of the laser spectroscopies of laser-induced breakdown spectroscopy (LIBS), laser-induced fluorescence (LIF) and FT-Raman, and the emerging, cutting edge technique of nonlinear optical microscopy (NLOM) in the modality of multiphoton excitation fluorescence (MPEF). The results obtained through this multi-analytical photonic approach were compared with those retrieved by examination of the surface and cross sections of the samples by OM and scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM–EDS). While the combination of LIBS, LIF and FT-Raman served to assess the composition of the various alteration layers, the use of MPEF microscopy allowed the non-destructive determination of the thicknesses of these layers, showing for both thickness and composition a good agreement with the OM and SEM–EDS results. Thus, the proposed approach, which avoids sample preparation, illustrates the capability of non-destructive, or micro-destructive in the case of LIBS, laser spectroscopies and microscopies for the in situ study of glass

Early November 1597. After an intense combat with four enemy ships, San Giacomo di Galizia (also known as Santiago), a just over 1000-ton galleon, enters the Ribadeo harbour in a terrible state, where it wrecks. This war vessel had been built in Naples in 1590 and sailed the Mediterranean and the Atlantic until it sank. In late November 2011, during an archaeological survey of the dredge area to improve the navigation of the ports in Galicia, a large ship was found and identified as the San Giacomo, which wrecked 414 years prior to its discovery. Several archaeological campaigns permitted a thorough record of the wreck and the recovery of hundreds of objects which this ship carried on its final journey. These artefacts included ceramics, metalwork, and wood, objects which reflected the activities that occurred on board during its short life. Combining an interdisciplinary approach based on artefacts, documents, and chemical analysis, the aim of this paper is to, on the one hand, attempt to reconstruct the sailing itinerary of the ship over its period of use and, on the other, to discuss how these commodities can help to write new narratives about the activities which occurred on board.

Silanes added during mortar or concrete preparation, may modify the fresh state properties, hydration kinetics and mechanical strength of the final product. The effects of silanes on cement hydration have been widely studied in the literature, however, there is some controversy about its effect at short ages. The present study was undertaken to determine the effect of a TEOS-based alkoxysilane (UCA-T), produced by ultrasound-assisted pre-hydrolysis of an oligomeric precursor, on early age cement paste hydration. The nature of the processes modifying the various stages of cement hydration kinetics in the presence of the alkoxysilane was ascertained by analysing paste composition at several ages (defined on the grounds of calorimetric curve results) using XRD, TG-DTG, FTIR and Raman spectroscopy. The calorimetric curve of pastes containing UCA-T exhibited a new early age, pre-induction period exothermal peak, indicative of UCA-T hydrolysis, C(3)A and C3S dissolution and ettringite and C-S-H gel precipitation. Portlandite, however, did not precipitate but reacts with the Si(OH)(4) sourced from UCA-T hydrolysis to generate further C-S-H gel. The induction period following on that new exothermal peak was considerably longer than the period observed in the reference cement, an effect that intensified at higher UCA-T content.

Admixtures used in concrete are natural or artificial compounds which are added in the kneading water to improve some properties of the fresh and the hardened concrete, such as durability, workability, mechanical strength, etc. Admixtures are classified according to modified properties and are defined as plasticizers, air entrainers, accelerators, retarders or superplasticizers and are added in concentrations below 1%. Due to the low concentration of admixtures it is difficult to monitor them after the interaction with the cement particles. This work is focused on a methodology to study a superplasticizer admixture based in polymerized melamine with Raman Spectroscopy and Surface Enhanced Raman Spectroscopy (SERS). The admixture is commercialized as a transparent liquid of high density where the polymerized melamine is dissolved. A drop of admixture has been heated at 40ºC degrees during four hours to evaporate the solvent; the quantity of the solid in the commercial admixture has been calculated at 21% in mass. The polymerized melamine has been analyzed with Raman spectroscopy before and after a heating treatment at 40ºC, thereby Raman spectrums of the admixture have been obtained as liquid and as solid. Besides, a SERS study of the same molecule has been done analyzing the commercial liquid admixture, and the solid left after the heating treatment by diluting the polymerized melamine in distilled water at 21% in mass. Results indicate that the polymerized melamine is not degraded during heating treatment, besides, Raman spectrum show signals which below to the aromatic ring at the melamine and other signals which correspond to the polymer. It has been tested that SERS technique is viable for the analysis of polymerized melamine as superplasticizer admixtures in the experimental conditions considered, being possible to identify characteristic signals of the aromatic ring of the melamine at 922 and 1030 cm-1.

Weathering steels are widely used in civil engineering, architecture and contemporary art due to their mechanical properties, their enhanced resistance to atmospheric corrosion as well as their aesthetic properties. Artists and blacksmiths often apply chemical treatments to obtain the appealing colors of a patina in a shorter period of time. However, the development of an accelerated patina may have an effect on the final appearance and color of the surface. With the aim of evaluating differences in color and studying the evolution of the surface, eight accelerated patinas were made and exposed to the atmosphere for periods of time of up to 24 months and were compared to a natural patina. The characterization studies showed the presence of lepidocrocite on the surface. A close inspection of the X-ray diffraction patterns showed the displacement of the (020) lepidocrocite reflection and asymmetric broadening of selective lines of this phase that were associated to stacking and twins faults, respectively. These faults decrease with the exposure time and are related to a maximum at 630 nm in the reflectance spectrum and the stabilization of the b* coordinate (yellow color). The colors of the accelerated patinas differ from the natural patina at short exposure times. However, they tend to converge at longer exposure times.

Priming techniques such as magneto-priming are being broadly used in several studies focused on enhancing seed germination. Simultaneously, researchers have been performing tests on many species using PEG and NaCl, which generate osmotic stress conditions, proving that germination parameters are considerably delayed. The microscopic structure of seeds can be investigated using the Micro-Raman spectroscopic technique. The effects of magneto-priming and osmotic stress on the Triticale seed germination were studied with regards to the compounds identified in the pericarp, germ and endosperm using Micro-Raman. It was proved that Micro-Raman with magneto-priming together is a convenient approach to obtain and analyse information from the Triticale seed key components, mainly the ones in the endosperm. Although the response of the pericarp to this technique was feeble, generally the spectra ensued from the germ were rewarding. The identification of chemical compounds indicates that applying magnetism to seeds make them germinate earlier under stress conditions.

The study described sought further understanding of the synergies in a mix of CDW pozzolans, containing (calcareous and siliceous) concrete and glass waste, used to prepare ternary eco-cement paste bearing 7% of the binary blend at concrete/glass ratios of 2:1 and 1:2. The mineralogical phases in the 2-day, 28-day and 90-day cement matrices were identified and monitoret using XRF, XRD-Rietveld, SEM-EDX, FT-IR, and NMR. The findings showed that changes in the reaction kinetics in the ternary blended pastes relative to OPC pastes depended on the nature of the recycled copncrete and the glass content. Adding the binary mix bearing clacareous concrete ( at a ratio of 2:1) favoured ettringite, portlandite, and amorfous phase formation, whilst the blends with siliceous concrete favoured CSH gel formation. Monocarboaluminate was detected in the 90-day siliceous concrete anbd glass pastes in amounts similar to those found in the reference OPC paste.

The arrival of Christopher Columbus in America stimulated the creation of new settlements in which the materials and construction methods coming from Spain and those existing in the area were used. The first village built was La Isabela (1494) where the Spaniards found good limestone for ashlars and were able to make lime as well as good clay for earth walls, masonry walls, etc. After La Isabela, the cities of La Vega (1495) and Santo Domingo (1498) were established. These villas still include vestiges of these building materials that are a source of information about their composition. The study is focused on the ruins of the fortress of Concepcion de La Vega that survived the earthquake in 1562 that destroyed the city. The aim of this research was to characterize the mortar and plasters of the fortress of Concepcion de La Vega on the Hispaniola Island. To determine their chemical and mineralogical composition optical microscopy (OM), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy and a thermogravimetric differential thermal analysis (TG-DTA) were used. The results showed that the major component of the mortars was CaCO3 (95 %), indicating that there is lime mortar. The plaster is lime based with iron oxide.

Portland cement concrete is considered, since being adopted by modern architecture in the twentieth century, a `noble¿ material, the latest to join the list of built heritage materials. For correct conservation of cement concrete, including the selection of compatible protective treatments, the determination of constitutents that can influence, cause or be the result of deterioration phenomena is of fundamental importance. However, components found in low concentrations, such as organic aditives, are difficult to detect with the most common concrete research­ and industry­driven analysis. In heritage science, surface­ enhanced Raman spectroscopy(SERS) has become a very useful molecular identification technique for the detection of organic molecules at very low concentrations provided by the physical effect known as surface plasmon localization. This effect occurs when the molecule is in close contact with metallic nanostructures upon resonant laser irradiation. In this work, the first approach for the development of a new "in situ" SERS sensor for Portland cement concrete is presented using a simplified system based on the main product of the hydration of Portland cement, a calcium silicate hydrate (C­S­H). Thereby, C­S­H with and without Ag were synthesized and irradiated by nanosecond ultraviolet and visible laser pulses for the detection of a model organic molecule, rhodamine B in low concentration (10­-6 M), a traditional analyte in SERS studies. The results of SERS analysis showed a high amplification of the rhodamine Raman signal in substrates irradiated by laser.

The calcium silicate hydrate gel (C–S–H) was synthesized by the double decomposition method because of the simplicity and the quickness of the procedure. The structure of the C–S–H gels after 1 week and 4 weeks in contact with the formation solution was studied through micro-Raman, Fourier transformed infrared spectroscopy and 29Si nuclear magnetic resonance. Simultaneous thermodifferential–thermogravimetric analysis and mass spectrometry (DTA/TG/MS) was used to identify the amount of calcium carbonate formed due to the reaction between the calcium and atmospheric CO2. With DTA/TG/MS, mass loss due to CO2 was observed to take place at temperatures below 400 °C, unidentified to date, which might be associated with the CO2 adsorbed on the C–S–H gel. Thus, in the TG analysis in the 300–430 °C range, both the loss of water due to the decomposition of the amorphous calcium carbonate and the loss of CO2 adsorbed on the gel must be considered. Additionally, polymerization of the gel and a decrease in the Ca/Si ratio was observed from the samples from 1 to 4 weeks.