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The mineralogical composition of archaeological pottery is closely related to the raw material and the firing conditions, thus constituting a source of information both on the origin and the manufacturing technology of ceramic artefacts. The techniques used to clarify the composition of the ceramic material from the point of view of the mineralogical phases include X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and petrographic analysis. Such techniques normally require the taking of a sample from the object, thus often limiting their applicability to sherds rather than intact vessels. The present study aims to investigate the possibility of applying reflection FTIR spectroscopy in the mid- and near-IR to the non-invasive analysis of the mineralogical composition of archaeological pottery, with reference to a set of Etruscan ceramic materials from the excavation of Tarquinia (Italy). [ABSTRACT FROM AUTHOR]

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 monitored 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 concrete and the glass content. Adding the binary mix bearing calcareous concrete (at a ratio of 2:1) favoured ettringite, portlandite, and amorphous phase formation, whilst the blends with siliceous concrete favoured C-S-H gel formation. Monocarboaluminate was detected in the 90-day siliceous concrete and glass pastes in amounts similar to those found in the reference OPC paste. [ABSTRACT FROM AUTHOR]

The particulate matter (PM) in the atmosphere may be composed of many elements and compounds, including toxic species and hazardous materials, which demand effective control of its emissions, starting with the knowledge of the sources. In this sense, the mineralogical analysis of the PM might be a powerful tool. Here, we present a comprehensive mineralogical characterization of the coarse and fine PM in an industrialized city southeast of Brazil, including a discussion about the transport, deposition, and potential sources associated. Elemental and mineralogical analyses by EDXRF and RSr-XRD were performed on SPM, TSP, PM10, and PM2.5. The results showed distinct mineralogical composition depending on the PM size. Mineral phases in SPM and TSP were majorly composed of hematite and quartz, while PM10 and PM2.5 were majorly composed of carbon, halite, sulfates, and carbon. The results show hazardous mineral phases associated with respiratory injuries in all PM size classes, such as hematite, pyrite, EC, and quartz. The XRD analysis also revealed primary particles of sulfate in the region close to industrial sources. [ABSTRACT FROM AUTHOR]

Cement or clinker phase quantification is considered as an important task for the control of the cement quality and its manufacturing conditions. Indeed, precise clinker phase quantification allows the prediction of cement properties and the identification of possible anomalies during its production process. However, the complexity of cement and clinker mineralogy makes this step very difficult. In this work, a study was carried out to quantify the mineralogical phases of four Portland cements and two clinkers using two different methods: The first is the traditional Bogue method and the second is X-ray diffraction coupled with Rietveld refinement. The comparison method results showed that the Rietveld method is the most precise and powerful tool for cement and clinker phase quantification since it takes into account the minor phases such as gypsum, anhydrite, and hemihydrate and differentiates between the polymorphism varieties of cement phases (M1 alite, M3 alite, β belite, and γ belite). However, it was shown that Bogue calculation remains a primary estimation method of only the major clinker phases (C3S, C2S, C3A, and C4AF). Only for calcite amount must be better estimated by thermogravimetric technique or calcimetry method than Rietveld method, since there is an overlapping of the peaks of calcite and alite. [ABSTRACT FROM AUTHOR]

Ferruginous concretions or lateritic debris are environmental liabilities of the nickel industry in Moa. This article states the thermodynamic study of samples concretions of Moa occidental deposit (Zone A), used in decarbonizing ACI HK40 steel produced in an electric arc furnace. The samples of granulometric fractions were characterized by using fluorescence X-ray techniques and X-ray diffraction. The results reveal the existence of mineralogical iron phases such as maghemite and goethite, in correspondence to contents of iron oxide (III). The thermodynamic study focused on the reactions that can occur in the metallic bath when the material is added to the furnace. It was predicted that between the 1 573 K and 1 973 K the decarburization reaction is not possible with the silicon, manganese and aluminum oxides contained in the debris, which become part of the slag; while iron oxide (II), works as an oxidant of carbon and other impurities on the molten metal bath. The experimental tests were developed at industrial scale and thermodynamic study forecasts were corroborated and the possibility of using particles larger than 2 mm as oxidants during the decarburization stage of ACI HK-40 steel, without affecting the chemical composition required for the alloy. [ABSTRACT FROM AUTHOR]

The sintering of chromium-containing vanadium-titanium magnetite using different coke contents was studied through the sintering pot tests, X-ray diffraction analysis and mineralogical phase analysis. Results showed that, as the coke content increased from 3.2% to 4.4%, the liquid phase and combustion zone thickness increased while the vertical sintering rate and ratio of sintered product decreased. In addition, the combustion ratio of exhaust gas also increased with increasing the coke content, indicating that combustion zone temperature also increased, and the excessive the coke content in the sintering process of vanadiumtitanium magnetite is harmful. As the coke content increased, the magnetite, silicates, and perovskite contents of the sintered ore increased while the contents of hematite and calcium ferrite of sintered ore decreased; drum strength decreased, and reduction degradation properties increased while reduction ability decreased. We found that the appropriate coke content for the sintering process is 3.6 wt%. [ABSTRACT FROM AUTHOR]

Chengde chromium-bearing vanadium-titanium magnetite (CCVTM) has been used as an important mineral resource in sinter making. The MgO content of this sinter can be enhanced by adding dolomite, which improved operation of the blast furnace. The effects of MgO in the form of dolomite on metallurgical properties, microstructure and mineral compositions of CCVTM sinter were studied by a sinter pot test, X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), and mineral phase microanalysis. The results were as follows: The flame front speed and sinter coefficient decreased with an increase in MgO content from 2.66 to 3.86% by adding dolomite. With an increase in MgO content from 2.66 to 3.86%, the flame front speed, sintering utilization factor, and the value of RI decreased, while RDI and the softening-melting properties improved. In addition, the value of sinter strength (TI) reached a maximum value at MgO = 3.56%. In addition, an increase in the abundance of magnetite, magnesium ferrite, and silicate phase, as well as a decrease in hematite, was found with an increase in MgO content. We concluded that the most appropriate MgO content in the sinter is 3.56%. [ABSTRACT FROM AUTHOR]

High-chromium vanadium and titanium magnetite (HCVTM) sinter has poor properties. The coke ratio has an important effect on the behavior of HCVTM sintering as it affects the mineral phases in the high-chromium vanadium and titanium sinter (HCVTS) via changing the sintering temperature and atmosphere. In this work, the sintering behavior of HCVTM mixed with varying coke ratios was investigated through sintering pot tests, X-ray diffraction (XRD), gas chromatographic analysis, and mineral phase analysis. The results show that, with the increase of the coke ratio from 4.0% to 6.0%, leading to the increase of the combustion ratio of the flue gas, the vertical sintering rate and sinter productivity decrease. Meanwhile, with the change of the coke ratio, the content of magnetite, silicate, and perovskite increase, while the hematite and calcium ferrite decrease. In addition, the tumble strength and reduction ability of HCVTS decrease, and its degradation strength increase. It was found that the appropriate coke ratio for the sintering process was 5.0 wt %. [ABSTRACT FROM AUTHOR]

At present, the dealkalization and comprehensive utilization of red mud is a worldwide problem. Studies on the settling performance and phase transformation of red mud by HCl, CaO, and HO leaching are limited. In this study, the characteristics of red mud were systematically analyzed. The average sizes of graded and initial red mud were 4.11 and 9.20 μm, respectively. X-ray diffraction (XRD), X-ray fluorescence spectra (XRF), and thermogravimetry-differential scanning calorimetry (TG-DSC) results indicated the different mineralogical phases, composition, and thermal behavior. The addition of HCl could neutralize the alkalization in the red mud slurry, and CaO could replace the Na and K. Notably, the pH of the red mud slurry had no obvious change with the increase in water washing times in a certain pH. Interestingly, soluble Al and Fe were not detected in the HCl-red mud and CaO-red mud. In addition, the settling ratio was used to express the settling performance of the red mud slurry. Their interaction mechanisms were proposed, which may include phase transformation and the changing of the size and surface area. The research provided a better understanding of the phase transformation and settling performance in the treatment of red mud by HCl, CaO, and HO leaching. [ABSTRACT FROM AUTHOR]

Highlights: [•] In TPC cement (APS/FA) predominates carboaluminate phase. [•] In OPC cement is formed ettringite as main phase. [•] Different morphologies and crystal sizes founding both cements. [•] The formation of non-expansive ettringite inside the pores is identified. [•] The TPC and OPC pastes can be catalogued as resistant to sulphate ions. [Copyright &y& Elsevier]

Abstract: This paper presents for the first time the influence of mixing different thermally activated paper sludges (APS) and fly ash (FA) on the pozzolanic reaction kinetics in APS–FA–Ca(OH)2 systems as a previous step to manufacture the future commercial ternary blended cements. In this study, two paper sludge wastes from different origins and activation conditions (laboratory (LS) and industrial (IS) scale) have been investigated, once mixed with fly ash at a ratio of 1:1 by weight. The results indicated that binary blends of pozzolans exhibited a high pozzolanic activity, showing that the hydrated phases produced during the pozzolanic reaction depend on the origin and activation conditions of clay wastes. At all times of reaction, the predominant phase turn out to be the LDH structures when LS pozzolan was used; meanwhile for the IS pozzolan the along with the LDH were the main phases during the first 28days. [Copyright &y& Elsevier]

Abstract: The Fourier Transformed Infrared (FTIR) spectra analysis of two fluxes used in the thin slab casting process of steel were carried out in order to identify the mineralogical species present in fluxes as received and after a heat treatment to 1573K and further solidification at two different cooling velocities. Fluxes as received show the presence of wollastonite (CaO·SiO2) and a sodium carbonate (Na2CO3) as the main components; after the heat treatment, there was almost a whole transformation from the original compounds to cuspidine (3CaO·2SiO2·CaF2) and nepheline (Na2O·Al2O3·2SiO2) phases. These results were confirmed by X-ray powder diffraction (XRD) to the slowly cooling velocity. The FTIR technique is proposed as a useful and complementary technique to X-ray diffraction to study the structure of commercial fluxes for thin slab casting. [Copyright &y& Elsevier]

Abstract: A great amount of mineralogical phases were predicted and represented in stability phase diagrams, which were obtained by the use of the thermodynamic software FACTSage considering both the chemical composition and the melting temperature of the mould flux. Melting-solidification tests on commercial mould flux glasses for thin slab casting of steel revealed the existence of cuspidine (Ca4Si2O7F2) as the main mineralogical phase formed during the flux solidification by X-ray powder diffraction (XRD). This phase directly influences the heat transfer phenomena from the strand to the mould and it is obtained with higher fluorite content (22% CaF2). Cuspidine is desirable only in fluxes to produce medium carbon (included peritectic grade) steels, because it reduces the heat flux from the strand to the mould, thus controlling the shrinkage rate during the flux solidification. The experimental results are in agreement with those obtained by the thermodynamic software. The stability phase diagrams could be used as an important tool in the flux design for continuous casting process. [ABSTRACT FROM AUTHOR]

Abstract: Melting-solidification tests on continuous casting commercial mould flux glasses for low carbon (0.015–0.06% C) and medium carbon steels (0.07–0.1% C) revealed the existence of abundant mineralogical phases formed during the flux solidification; some important mineralogical species were identified by X-ray powder diffraction (XRD). Among the most important species found are the cuspidine (Ca4Si2O7F2) and nepheline (NaAlSiO4). These species directly influence the heat transfer phenomena from the strand to the mould. The thermodynamic software FACTWIN was used to predict the phases formed in the fluxes considering both the chemical composition and the experimental melting temperature of the mould flux. A change in the fluidizing effect of CaF2 was observed when the species content is higher than 12%. The phases predicted with the thermodynamic software are in agreement with those identified by XRD. It was found that cuspidine is desirable only in fluxes to produce medium carbon (included peritectic grade) steels, because it reduces the heat flux from the strand to the mould, thus controlling the shrinkage rate during the flux solidification. Liquid fluxes are required to produce low carbon steels, therefore the formation of the nepheline phase is desirable since it melts at low temperature (1073K). [Copyright &y& Elsevier]

Abstract: In the study, the possibility to use nepheline-syenite, as fluxing agent, in a body mix used for porcelain stoneware tile, was determined. Starting from the reference mix composition, different amounts, 5.0, 10.0 and 15.6wt.%, of sodium feldspar were replaced with the same amounts of nepheline-syenite. Different sintering cycles were used to understand the role of the nepheline-syenite in the development of the final microstructure. The presence of nepheline-syenite strongly favours the sintering behaviour, by reducing the sintering time necessary to reach the water absorption values, requested by the International Standard. Furthermore, the microstructure results more homogeneous and the mechanical characteristics are increased. The better mechanical performances can also be attributed to the different mineralogical compositions, in particular with lower amount of glassy phase, higher flexural strength values are obtained. [Copyright &y& Elsevier]

Abstract: A monitoring system has been developed to characterize the bottom sediments of Lake Balaton. Samples were collected inside of the lake, from the top layers to 60 cm in depth. The samples were dried at room temperature and then sieved through 2-mm and 63-μm sieves. The total concentration of elements was measured by atomic absorption spectrometry (AAS) with an RSD of <5% from solutions. The determination of the mineralogical phase composition of sediments was carried out by X-ray powder diffraction (XRD). The main constituents of samples were quartz, calcite, mica, dolomite, chlorite, feldspar, smectite, kaolinite, pyrite and some amorphous materials. Ten elements were investigated, and Ni, Cr and Zn were chosen to be discussed in details. Results were compared with Hungarian soils, geochemical background values, sediment quality values (SQVs) and sediment background values (SBVs). Records showed that the average concentration of elements was usually less than that of SQVs and other background values for soils. However, some high concentrations at different sampling sites and depths surpassed the geochemical background values. Based on the results, it can be confirmed that the quality of the sediment inside Lake Balaton is satisfactory. [Copyright &y& Elsevier]

The influence of fuel level on Russian vanadiferous titanomagnetite sinter properties, productivity, and mineralogy are researched by sintering pot testing, metallographic microscopy, scanning electron microscopy analysis, and energy dispersive spectrometer (SEM-EDS) analysis. A comprehensive index is evaluated in conjunction with the same indexes and significance coefficient as that in the Panzhihua Iron and Steel Group. Results show that with the increasing fuel level from 3.5% to 6.0%, flame front speed, yield, tumbling test index (TI), and productivity, all first increase and then decrease. The low temperature reduction degradation index (RDI+3.15) and softening zone (ΔT) gradually increase while the RI and starting temperature of softening (T10), and ending temperature of softening (T40) decrease with increasing fuel levels from 3.5% to 6.0%. With the increase of fuel level from 3.5% to 6.0%, the content of FeO, SiO2, and MgO increase, while TiO2 shows a decrease. For the same increase in fuel level, the number of pores and calcium ferrite and hematite decrease but the silicate increases. In addition, in the fuel level range of 3.5% to 5.5%, magnetite correspondingly increases but then shows a drop after 5.5%. Moreover, when the fuel level increases to greater than 5.0%, FeOx and fayalite quickly increase and a small amount of metallic iron appears under the fuel level of 6.0%. Overall, the optimal fuel level under current production conditions and indicator selection is 4.0%. [ABSTRACT FROM AUTHOR]

Converting construction and demolition waste (CDW) into secondary raw materials is one of the priorities of environmental policy and circular economy strategy. This study analysed the variation in eco-efficient paste reactivity with OPC replacement ratio (5% to 10%) and hydration time (2 d, 28 d and 90 d). Three types of CDW were explored: two (calcareous and siliceous) consisting of fine (<5 mm) concrete waste and one in laminated glass (<40 mm). Further to the mineralogical phases identified at the aforementioned percentages, the four materials, i.e., the three types of CDW-blended cements and the OPC reference, were similarly reactive. The primary hydration products, C-S-H gels, C 4 AH 13 and C 4 AcH 11 , ettringite and portlandite, were the same as observed in OPC hydration. These findings attest to the scientific viability recycling such CDWs as mineral additions in eco-cement manufacture and consequently eliminating the need for stockpiling these materials at recycling/storage plants. [ABSTRACT FROM AUTHOR]

This study aimed at laying the groundwork for a compendium on mineralogical phases responsible for the colors and opacity of ancient glasses, with specific reference to mosaic tesserae. Based on the awareness that a comprehensive database of these phases is currently lacking in the available literature, this compendium foresees two main objectives. The first scope was to set the basis for a well-structured database, as a reference point for scholars from different backgrounds for comparative and methodological purposes. The second goal was to provide insights on analytical methods that could be profitably used for achieving an in-depth characterization of coloring and opacifying inclusions; a tailored multi-analytical approach based on easily accessible and widespread techniques like OM, SEM-EDS, μ-Raman, and XRPD is proposed here. Micro-structural and compositional features of glass tesserae, where different types of crystalline phases were detected (Sb-based, Sn-based, Cu-based, Ca-phosphate-based) are presented in well-structured synoptic tables, following a summary on historical–archaeological information on their use. [ABSTRACT FROM AUTHOR]