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This study presents the results of new research into Etruscan technology for earthen architecture as well as ceramic production in the upper Tiber Valley in central Italy, using as a case study the Etruscan settlement of Col di Marzo (Perugia). It determines the compositional differences of the raw material employed as building material and for ceramic production by X‐ray powder diffraction (XRD), thermogravimetric analysis and differential thermal analysis (TG‐DTG), Fourier‐transform infrared analysis (FTIR) and geotechnical analyses. The research also advances the knowledge of ceramic manufacturing technology, with a focus on impasto production, at Col di Marzo between the fifth and mid‐third centuries bce and the surrounding territory on the left bank of the River Tiber. The compositional analysis of building material compared with the ceramics provides answers to questions related to their sourcing and deepens the understanding of the exploitation of natural resources. [ABSTRACT FROM AUTHOR] more...

High-molecular-mass polymeric polyphenols (HPPCs) is the major group of polyphenols in red wine. However, owing to the diversity and structural complexity, its compositional characterization remains a difficulty. In this study, purified high-molecular-mass polymeric polyphenols (PHPPCs) was isolated by solid phase extraction combined with semi-preparative HPLC from red wine. Different chemical degradation methods (NaOH, HCl and benzyl mercaptan degradation) were used to decompose the PHPPCs into low molecular weight fragments. The chemical structures of the degradation fragments were verified by HPLC/UPLC−DAD and HPLC-FT-ICR-MS. The results showed that three proanthocyanidins, five proanthocyanidins benzylthioether, quercetin and fifteen anthocyanins were detected by degradation in the presence of benzyl mercaptan. Nine bound phenolic acids were found by NaOH degradation and twelve bound amino acids were proved by HCl. Among these different fragments detected,delphinidin-3-O-glucoside pyruvic adduct, four acylated anthocyanins, four hydroxyphenyl pyranoanthocyanins, quercetin, protocatechuic acid, vanillic acid, and cinnamic acid were first found in the PHPPCs. For the first time amino acids as constitutive units of polymeric polyphenols in red wines were verified. Based on the degradation fragments, the possible compositional characterization of HPPCs in red wine was postulated. Unlabelled Image • Purified high-molecular-mass polymeric polyphenols in red wine were obtained. • Chemical degradation methods were used to analyze the structure of PHPPCs of red wine. • Anthocyanins monomers degraded from PHPPCs were speculated by LC-FT-ICR MS. • The possible compositional characterization of PHPPCs in red wine was postulated. [ABSTRACT FROM AUTHOR] more...

• Bricks from Hagia Sophia (Istanbul, Turkey) were analyzed by OM, XRF, XRPD, TGA and SEM-EDS. • An innovative micro-EDS approach on the matrix of the bricks showed that different clays were used in different building phases. • The compositional analogy between the bricks from Hagia Sophia (Istanbul, Turkey) of the 6th and 14th centuries has been highlighted. The work shows the results of a multi-analytical study performed on twenty-nine brick samples taken from Hagia Sophia in Istanbul (Turkey). Hagia Sophia, one of the most important historical buildings in the world, has a very complex construction history. This complexity is also reflected in the materials that were used for its construction. The main purpose of this work is to verify whether there are any compositional differences in the bricks used in different historical periods, but also to understand the reasons for any compositional differences between one period and another. The samples were studied by optical microscopy (OM), X-ray fluorescence (XRF), X-ray powder diffraction (XRPD) and thermogravimetric analysis (TGA), coupled with a new approach, based on the micro-chemical EDS analysis used to obtain information on the clay fraction of the matrix. The study showed that, most probably, the differences between the bricks belonging to the different construction phases are due to the composition of the clays used for their preparation. [ABSTRACT FROM AUTHOR] more...

Abstract Organic phosphorus (P o) constitutes the most important fraction of P in lake sediments, and the compositional properties of P o affect its behavior in lake ecosystems. In this study, 31P NMR, FT-IR spectroscopy, and UV–visible absorbance spectroscopy were combined to identify the dynamic composition of sediment P o across two sets of lakes in China ranging from oligotrophic to eutrophic, and their possible effects on lake eutrophication were evaluated. The results showed that sediment P o content (accounting for 24–75% of TP) was positively correlated with trophic status in both Eastern Plain and Yun-Gui Plateau lakes of China, and the linear relationship was more stable compared to total P (TP), implying that sediment P o may be a superior indicator of trophic status than TP. The P o component, phosphonate accounted for only 0.4% or less of P o , while the monoester P and diester P, accounted for 2–24% and 0.5–5% of P o , respectively, and were the main factors causing P o to increase with the increasing trophic status. The factors were closely related to the enhanced organic sewage load and intensification of contemporary sedimentation of phytoplankton. As trophic status increased, sediment P o might integrate into larger amounts of aromatic substances and functional groups, which could enhance the stability of P o in sediments. Furthermore, sediments from lakes with higher trophic status exhibited a higher degree of humification and molecular weights, which impart resistance to biodegradation, and therefore, reduced the risk of sediment P o release. However, the massive accumulation of bioavailable P o (monoester and diester P) allows possible degradation, supporting algal growth and maintains eutrophic status because there is abundant alkaline phosphatase in eutrophic lakes. Thus, to control lake eutrophication more effectively, targeted actions are urgently required to reduce the accumulation and degradation of P o in lake sediment. Graphical abstract Unlabelled Image Highlights • Multiple methods were used to characterize sediment P o. • Sediment P o may be a superior indicator of lake trophic status than TP. • Sediment bioavailable P o increased with increasing trophic status. • Abundant aromatic substances, functional groups, and high humification enhance sediment P o stability in eutrophic lakes. [ABSTRACT FROM AUTHOR] more...

A procedure for compositional characterization of a microalgae oil is presented and applied to investigate a microalgae based biodiesel production process through process simulation. The methodology consists of: proposing a set of triacylglycerides (TAG) present in the oil; assuming an initial TAG composition and simulating the transesterification reaction (UNISIM Design, Honeywell) to obtain FAME characterization values (methyl ester composition); evaluating deviations of experimental from calculated values; minimizing the sum of squared deviations by a non-linear optimization algorithm, with TAG molar fractions as decision variables. Biodiesel from the characterized oil is compared to a rapeseed based biodiesel. more...

Lithium titanate is a proposed tritium breeding blanket material in D-T based fusion reactor under International Thermonuclear Experimental Reactor programme. For optimization of sol-gel preparation method and chemical quality control, compositional characterization of LiTiO was carried out by particle induced gamma-ray emission using 8 MeV proton beam at BARC-TIFR pelletron facility. For the first time, a non-destructive method has been standardized for simultaneous determination of Li, Ti and O in this ceramic sample, which is otherwise difficult by various wet-chemical as well as radio-analytical methods. Thick targets of samples, synthetic samples and standards prepared in graphite matrix were used for the experiment. Rutherford backscattering spectrometry method was used for beam current monitoring using a thin Au foil. The gamma-rays at 478, 983 and 6129 keV from Li(p, p′γ)Li, Ti(p, p′γ)Ti and O(p, p′γ)O nuclear reactions, respectively, were measured using high resolution gamma-ray spectrometry and corresponding peak areas were used for concentration calculations by relative method. [ABSTRACT FROM AUTHOR] more...

Organic phosphorus (P o) plays a very important role in the process of lake eutrophication, but there is still a lack of knowledge about the internal cycle of P o in suspended particulate matter (SPM) dominated by algal debris. In this study, the characterization of bioavailable P o by sequential extraction and enzymatic hydrolysis showed that 45% of extracted TP was P o in SPM of Lake Dianchi, and 43–98% of total P o in H 2 O, NaHCO 3 and NaOH fractions was enzymatically hydrolyzable P o (EHP, H 2 O−EHP: 31–53%). Importantly, labile monoester P was the main organic form (68%) of EHP, and its potential bioavailability was higher than that of diester P and phytate-like P. According to the estimation of P pools in SPM of the whole lake, the total load of P i plus EHP in the H 2 O extract of SPM was 74.9 t and had great potential risk to enhance eutrophication in the lake water environment. Accordingly, reducing the amount of SPM in the water during the algal blooming period is likely to be a necessary measure that can successfully interfere with or block the continuous stress of unhealthy levels of P on the aquatic ecosystem. [Display omitted] • 45% of total extracted TP was P o in SPM of Lake Dianchi. • The total EHP contents accounted for 43–98% of P o in three extracts in this study. • Labile monoester P was the main organic form of EHP and had higher bioavailability. • The abundant H 2 O−P i and H 2 O−EHP had great potential risk to the aquatic ecosystem. [ABSTRACT FROM AUTHOR] more...

The k-based internal mono-standard prompt gamma-ray neutron activation analysis (IM-PGNAA) method was used for compositional analysis of a cement standard provided by the International Atomic Energy Agency as a part of inter-laboratory comparison exercise. The PGNAA was also applied to a local cement sample for comparison purpose. The concentration ratios of elements with respect Ca were determined using the internal mono-standard method. The concentration ratios were then converted to the absolute concentrations by determining concentration of Ca in the cement using relative method. Concentrations of 11 elements were determined in both sample and standard of cement. The results of cement standard are found to be in good agreement with the certified values. The uncertainties on the elemental concentrations were in the range of 5-10 %. [ABSTRACT FROM AUTHOR] more...

Abstract: Total-reflection X-ray fluorescence spectrometry has been compared with Instrumental Neutron Activation Analysis in order to test its potential application to the study of archaeological ceramics in the archaeometric field. Two direct solid non-chemical sample preparation procedures have been checked: solid sedimentation and solid chemical homogenization. For sedimentation procedure, total-reflection X-ray fluorescence allows the analysis of the elemental composition with respect to the size fraction but not the average evaluation of the composition. For solid chemical homogenization procedure, total-reflection X-ray fluorescence provides precise (from 0.8% to 27% of coefficient of variation) and accurate results (from 91% to 110% of recovery) for 15 elements (Cr, Hf, Ni, Rb, Al, Ba, Ca, K, Mn, Ti, V, Cu, Ga, Y and Fe) with an easy sample preparation process of the solid clay and without previous chemical treatment. The influence of the particle sizes has been checked by total-reflection X-ray fluorescence sample angle scans and anomalous behaviors have been found for three additional detected elements: As, Sr and Zn, which can be attributed to interference effects of the mineral grain sizes of their associated chemical phases in the total-reflection X-ray fluorescence interference region. The solid chemical homogenization procedure produces data useful for archaeological interpretation, which is briefly illustrated by a case-study. Finally, the decantation procedure data can be also useful for size chemical speciation and, consequently, for alternative environmental total-reflection X-ray fluorescence applications. [Copyright &y& Elsevier] more...

• The characteristics of historical mortars from a World Heritage Site were documented. • Binder and aggregates compositions are identical in varied locations of the monument. • b:a ratios vary significantly but granitic aggregates are in general well graded. • Three different compatible repair mortars are proposed for different locations. • A contribution for the knowledge on the constructive evolution is provided. The present research addresses the compositional and textural properties of bedding mortars from rubble stone masonries of a historic construction, built between 13th and 17th centuries and during different constructive periods (National Palace of Sintra, Portugal). The characterization of mortars established the basis for the formulation of compatible repair mortars. The mortars revealed similar composition and depended on the raw material locally available (calcitic binder and aggregates of granitic nature), whereas the textural features (b:a and aggregate gradation) varied significantly according to mortar use (interior/exterior walls; interior/exterior leaf of exterior walls). Statistical analysis on textural data allowed to propose different repair mortar formulations according to their use; one for interior walls (b:a ≈ 1:2) and two for exterior walls (b:a ≈ 1:3 and b:a ≈ 1:4). Besides, the research found consistent correlations between mortars' characteristics and the historical background of the monument although further analyses are required for a definitive link between masonries materials and the constructive periods. [ABSTRACT FROM AUTHOR] more...