Catholic social thought and teaching is sometimes conceptualised using an historical or principles-based approach. This paper proposes an alternative framing, construing Catholic social teaching (CST) as a multi-layered phenomenon that can be grouped into three broad tiers, each with a distinctive role. This framing is not intended to supercede the others, nor is it inconsistent with them. The proposal emerges out of a series of discussions hosted by the Catholic Agency for Overseas Development, a Catholic UK-based development agency, member of Caritas Internationalis, and an official agency of the Bishops’ Conference of England and Wales. The paper operates on two levels simultaneously: it attempts a distinctive reframing of CST using a distinctive source, and it attempts an enactment of CST methodologically and structurally. Construing CST as a multi-layered phenomenon that can be grouped into three broad tiers provides a clarity that empowers us in two ways. First, it clarifies the distinctive role of CST at each level. Second, it makes clear that CST is a work of the Spirit rather than a human phenomenon. Such an understanding of CST brings out with particular clarity a vision of the role, purpose, and even the agency of Catholic social thought in relation to a troubled world.

Layers of volcanic ash and Andosol soils derived from the ash may play an important role in preserving snow and ice as well as in the development of permafrost conditions in (a) the immediate vicinity of volcanoes at high elevations or at high latitudes and (b) land areas that are often distant from volcanic activity and are either prone to permafrost or covered by snow and ice, but have been affected by subaerial ash deposition. The special properties of volcanic ash are critically reviewed, particularly in relation to recent research in Kamchatka in the Far East of Russia. Of special importance are the thermal properties, the unfrozen water contents of ash layers, and the rate of volcanic glass weathering.Weathering of volcanic glass results in the development of amorphous clay minerals (e.g. allophane, opal, palagonite), but occurs at a much slower rate under cold compared to warm climate conditions. Existing data reveal (1) a strong correlation between the thermal conductivity, the water/ice content, and the mineralogy of the weathered part of the volcanic ash, (2) that an increase in the amounts of amorphous clay minerals (allophane, palagonite) increases the proportion of unfrozen water and decreases the thermal conductivity, and (3) that amorphous silica does not alter to halloysite or other clay minerals, even in the Early Pleistocene age (Kamchatka) volcanic ashes or in the Miocene and Pliocene deposits of Antarctica due to the cold temperatures. The significance of these findings are discussed in relation to past climate reconstruction and the influence of volcanic ash on permafrost aggradation and degradation, snow and ice ablation, and the development of glaciers.

Based on the open-source IIIF image viewer Mirador 3, the Specialised Information Service Art, Photography, Design - arthistoricum.net, in cooperation with NFDI4Culture, the consortium for research data on material and immaterial cultural heritage, provides a platform for collaborative exploration of image resources. Within the virtual research environment, users can create their own workspaces and image collections individually or in groups, share them for collaborative efforts, and jointly create persistent annotations. This article outlines the development and integration process of this web-based research platform and highlights future areas of improvement.

Deep sediments from the Red Sea have been studied extensively and provide a rich resource for understanding mineral transformations under hydrothermal conditions. Interrelationships among various sampling sites, however, are still rather incomplete. The purpose of the present study was to increase understanding of these systems by characterizing and comparing the Fe-Mn oxyhydroxides from the southern Atlantis II, Chain A, Chain B, and Discovery Deeps, using high-resolution transmission electron microscopy. Some of the hydrothermal sediments of Chain A are dominated by Si-associated Fe oxides (ferrihydrite, goethite, lepidocrocite, and short-range ordered, rounded particles) resembling the hydrothermal sediments of the SW basin in the Atlantis II Deep, indicating sub-bottom connections between the Deeps. Although some of the sediments of the Discovery Deep show a similar trend; short-range ordered, rounded particles were not detected in these sediments, implying that crystallization of this short-range ordered phase is sensitive to the Si/Fe ratio in the brine and only at elevated ratios does it crystallize out of the brine. Silicon-associated and Fe-enriched Mn oxyhydroxides such as groutite, manganite, todorokite, and Mn-dominated lathlike layers occasionally contain Ca and Mg impurities. Manganese substitutes for Fe and vice versa, leading to a solid-solution series between goethite and groutite and Mn-enriched ferrihydrite. Hematite is the only Fe oxide in the hydrothermal sediments that is found to be lacking in impurities, which is probably due to its formation by recrystallization from other Fe oxides.

Quantitative mineralogical analysis of clay-bearing rocks is often a non-trivial problem because clay minerals are characterized by complex structures and are often affected by structural disorder, layer-stacking disorder, and interstratification. In the present study, internal-standard Rietveld X-ray powder diffraction (XRPD) analyses were combined with X-ray fluorescence (XRF) chemical analyses for the mineralogical characterization and quantitative analysis of heterogeneous clay-rich sedimentary rocks that are involved in a slow-moving landslide in the Termini-Nerano area, Sorrento Peninsula (Italy), in order to investigate the relationship between the mineralogy of these rocks and landslides. Slow-moving landslides are usually considered to be associated with the more weathered and surficial parts of structurally complex slopes, and mineralogical analysis can help to clarify the degree of weathering of siliciclastic rocks. XRPD quantitative analyses were conducted by combining the Rietveld and internal standard methods in order to calculate the amounts of poorly ordered phyllosilicate clays (considered amorphous phases in Rietveld refinements) by difference from 100%. The vbAffina program was used to refine the amounts of mineral phases determined with XRPD using the element compositions determined by XRF analysis. XRPD analyses indicated that the samples mainly contain several different clay minerals, quartz, mica, and feldspars. Analysis of the clay fraction identified kaolinite, chlorite, and interstratified illite-smectite (I-S) and chlorite-smectite (C-S). The mineralogy of the materials involved in the landslide in comparison with the mineralogy of the “undisturbed” rocks showed that the landslide is located in the weathered realm that overlies an arkosic bedrock. The interstratified I-S and C-S occurred at landslide activity locations and confirmed that areas more susceptible to sliding contained the most weathered parts of the rocks and perhaps represent areas of past and currently active fluid flow.

LongYan kaolin has a large Fe content which affects the coloring. Bioleaching treatments to remove Fe impurities were conducted here using indigenous dissimilatory Fe(III)-reducing bacteria. The factors that affect bioleaching efficiency include bioleaching time, carbon source, pH, temperature, pulp density, and inoculum density and these were examined. Environmental scanning electron microscopy and X-ray diffraction were used to examine any textural or mineralogical changes at the surface of the kaolin that may have occurred during the bioleaching. Iron impurities in the kaolin were reduced from 0.88% to 0.48% with an increase in the natural whiteness index from 60.8% to 81.5% after 7 days of bioleaching treatment. A granulometric analysis of dispersed kaolin demonstrated that the bioleaching resulted in a decrease in particle size. The results demonstrated that the bioleaching was very effective at improving the quality of the kaolin, where insoluble Fe(III), either adsorbed to the kaolin surfaces or admixed as amorphous forms, was leached out by micro-organisms as water-soluble Fe(II).

Catalysts are very important in the use of cellulose, the main component of biomass, as a raw material for the large-scale production of liquid fuels and chemicals. 5-Hydroxymethylfurfural (HMF) is an extremely important intermediate in the fine chemical industry. HMF can be synthesized by acid-catalyzed dehydration of fructose, glucose, cellulose, or sucrose. The conversion of cellulose to HMF is challenging due to its chemical structure. The objective of the present study was to devise a more facile synthesis method using transition metal-doped montmorillonite catalysts (10Cr-Mnt, 10Cu-Mnt, 10Fe-Mnt, and 10Zn-Mnt) by wet impregnation. Samples were characterized by X-ray powder diffraction, specific surface area, and NH3-TPD analyses. The synthesized catalysts were used for the conversion of cellulose to 5-HMF in an aqueous medium. Among the metals studied, Cr showed the greatest catalytic activity. With the use of this catalyst, efficient conversion of cellulose to 5-HMF was achieved, affording a conversion yield of 93.47% and 5-HMF yield of 9.07% within 6 h at 200°C. The study described here could be useful for the efficient conversion of cellulose into 5-HMF, as well as into other biomass-derived chemicals.

The emergence of Sardis as an urban centre in the early Iron Age coincided with local production of fine painted pottery in a distinctive regional idiom. Examples of Lydian-style pottery found across western Anatolia from the eighth century BC attest the city’s growing cultural and economic contacts as well as consistent materials and craft methods. Archaeo- metric study using neutron activation analysis (NAA) at the University of Missouri Research Reactor (MURR) examined representative specimens of Lydian-style ceramics from Sardis and compared their composition with later examples of red-gloss and red-slipped pottery, fine grey wares and transport jars commonly found at the site. The results confirm the sustained activity of local workshops from the early Iron Age into later historical periods, as Lydia became part of the Seleucid and Roman empires and Sardis a centre of regional innovation.

Recently, significant advances have been made in the theory and application of acoustic and electroacoustic spectroscopies for measuring the particle-size distribution (PSD) and zeta potential (ζ potential) of colloidal suspensions, respectively. These techniques extend or replace other techniques, such as light-scattering methods, particularly in concentrated suspensions. In this review, we summarize acoustic and electroacoustic theory and published results on clay mineral suspensions, detail theoretical constraints, and indicate potential applications for the study of environmentally significant clay mineral suspensions. Using commercially available instrumentation and suspension concentrations up to 45 vol.%, acoustic spectroscopy can characterize particle sizes from 10 nm to 10 µm, or greater. Electroacoustic spectroscopy can determine the ζ potential of a suspension with a precision and accuracy in the mV range. Despite the clear potential for their use in environmental settings, to date, acoustic methods have been used mainly on clay mineral colloids with industrial application, typically combined with similar measurements such as isoelectric point (IEP) determined from shear yield stress or ζ potential from electrophoretic mobility measurements. Potential applications in environmentally relevant suspension concentrations are significant, as PSD and ζ potential are important factors influencing the transport of mineral colloids and associated contaminants through porous media. Applications include determining the effects of suspension concentration, surfactants, electrolyte strength, pH and solution composition on soil clay properties and colloidal interactions, and determining changes in PSD, aggregation and ζ potential due to adsorption or variations in the clay mineralogy.

Literature and history as objects of study and fields of inquiry have shaped each other in profound if asymmetrical ways. This introduction provides a brief account of how these disciplines intersect in the GAPE and the contemporary era, emphasizing concerns with expertise and amateurism that also emerge in many of the articles in this special issue. Those concerns, in turn, relate to what the articles show are literature’s pedagical functions in the GAPE and the present moment and within and beyond the classroom. As it argues, literature’s pedagogical dimensions challenge distinctions between teaching, research, and activism in the context of current debates about if and how historical and literary study should be presentist and politically committed.

The surface acidic properties of pillared clays (PILCs) with Al or Zr oxide pillars (prepared from a natural Portuguese smectite and a synthetic Laponite), and of a protonic NaHY zeolite, were studied by two methods: pyridine adsorption followed by infrared (IR) spectroscopy, and the catalytic transformation of 1-butene. The results of the pyridine adsorption revealed that all the pillared clays studied have mainly Lewis-type acidity, the exception being the clay pillared with Zr oxide, obtained from natural smectite, which also presents a significant number of Brönsted acid sites. The results of 1-butene transformation showed that the pillared clays exhibit catalytic properties similar to those of the protonic Y zeolite. The acid character of the solids was confirmed by the values of the cis/trans 2-butene isomers ratio. At short reaction times, product distribution showed that the main reaction is oligomerization, followed by cracking. After 15 min the products are mainly the linear isomers, cis and trans-2-butene, showing that the majority of the catalytic active sites, are already poisoned after 15 min of reaction. The particular behaviour of Laponite intercalated with Al oxide pillars is discussed. The IR spectra of the pyridine adsorbed on the fresh samples and after the catalytic assays, revealed that Lewis acid sites behave as active sites for 1-butene catalytic transformation. The consistency between the results of the two complementary techniques used for the characterization of the acidity of the solids was proved.

Electron energy-loss spectroscopy (EELS), energy-filtered transmission electron microscopy (EFTEM), and high-resolution transmission electron microscopy (HRTEM) have been applied in mineralogy and materials research to determine the oxidation states of various metals at high spatial resolution. Such information is critical in understanding the kinetics and mechanisms of mineral–microbe interactions. To date, the aforementioned techniques have not been applied widely in the study of such interactions. In the present study, the three techniques above were employed to investigate mineral transformations associated with microbial Fe(III) reduction in magnetite. Shewanella putrefaciens strain CN32, a dissimilatory metal-reducing bacterium, was incubated with magnetite as the sole electron acceptor and lactate as the electron donor for 14 days under anoxic conditions in bicarbonate buffer. The extent of bioreduction was determined by wet chemistry and mineral solids were investigated by HRTEM, EFTEM, and EELS. Magnetite was partially reduced and biogenic siderite formed. The elemental maps of Fe, O, and C and red-green-blue (RGB) composite map for residual magnetite and newly formed siderite were contrasted by the EFTEM technique. The HRTEM revealed nm-sized magnetite crystals coating bacterial cells. The Fe oxidation state in residual magnetite and biogenic siderite was determined using the EELS technique (the integral ratio of L3 to L2). The integral ratio of L3 to L2 for magnetite (6.29) and siderite (2.71) corresponded to 71% of Fe(III) in magnetite, and 24% of Fe(III) in siderite, respectively. A chemical shift (~1.9 eV) in the Fe-L3 edge of magnetite and siderite indicated a difference in the oxidation state of Fe between these two minerals. Furthermore, the EELS images of magnetite (709 eV) and siderite (707 eV) were extracted from the electron energy-loss spectra collected, ranging from 675 to 755 eV, displaying different oxidation states of Fe in the magnetite and siderite phases. The results demonstrate that EELS is a powerful technique for studying the Fe oxidation-state change as a result of microbial interaction with Fe-containing minerals.

The purification of clay minerals prior to their use as catalysts can escalate processing costs so methods are needed whereby less purification is necessary. One such potential method is acid treatment of the unpurified clay minerals. The main objectives of the present study were to develop the optimal acid-treatment conditions and to determine how the acidic properties of the modified clay samples influenced their catalytic capability toward the dehydration of ethanol and methanol. Clay mineral samples – allophane, palygorskite, and sepiolite, without purification – were acid treated (0.8 M HNO3; 95°C; 2, 8, or 24 h) and after calcination (500°C; 6 h) tested as catalysts for the conversion of methanol to dimethyl ether and of ethanol to diethyl ether and ethene. The changes in chemical and structural compositions as well as surface acidity of the mineral samples were analyzed and correlated with their catalytic performance. Among the samples studied, allophane was the most catalytically active in the dehydration of methanol to dimethyl ether. Acid treatment of this mineral sample decreased methanol conversion slightly. An opposite effect was found for ethanol dehydration to diethyl ether, where acid treatment increased catalytic activity of allophane. The differences in catalytic performance of the mineral samples were discussed with respect to the nature and concentration of acid sites.

The adsorption of the herbicides quinmerac 7-chloro-3-methylquinoline-8-carboxylic acid (QMe) and quinclorac 3,7-dichloroquinoline-8-carboxylic acid (QCl) on homoionic Fe3+-, Al3+-, Cu2+-, Ca2+-, K+- and Na+-exchanged montmorillonite was studied in aqueous solution. Adsorption data were fitted to the logarithmic form of the Freundlich equation. Ca- and Na-exchanged montmorillonites were ineffective in the adsorption of QMe. On the other hand, the QMe adsorption on Fe-exchanged montmorillonite was rapid and the equilibrium was attained after 15 min. An H-type isotherm was observed for the QMe adsorption on Fe-clay, indicating a high affinity of the solute for the sorption sites and almost complete adsorption from dilute solution. On the other hand, the adsorption isotherm of QMe on Al- and K-clay was of the S-type. This shape suggests that the solvent molecules may compete for the sorption sites. A Fourier transform infrared (FTIR) study suggested that the adsorption mechanism of QMe on Fe-, Al- and K-clay involves the protonation of QMe molecule due to the acidic water surrounding the saturating cations. The greater acidity of Fe-clay compared with Al- and K-clay explains both the lower QMe adsorption observed on Al and K systems and the lack of adsorption on Na and Ca systems. In contrast, the formation of a Cu complex permitted QMe to be adsorbed to a large extent to Cu-clay as shown by FTIR analysis. The QCl was adsorbed only by Fe-clay and the adsorption isotherm of QCl on Fe clay was of the S-type. This finding is consistent with the lower basic character of the QCl molecule nitrogen. In fact, the replacement of the electron-releasing methyl group in QMe with an electron-withdrawing Cl atom to form QCl makes the nitrogen lone-pair electrons of the quinoline ring unavailable for either protonation or complexation.

Fe is a common substituent in palygorskites (Plg), but its effect on the microscopic properties is unclear. In the current study, molecular dynamics (MD) simulations were carried out to investigate the effect of Fe on the properties of the nano-pores in Plg. The structures and dynamics of water and Na+ ions in the pores were computed by analyzing the MD trajectories. The results revealed that for both Fe-containing and ordinary Plg, zeolitic water molecules can diffuse into the pores with very low mobility whereas Mg-coordinated water fails to escape. Na+ ions show no obvious diffusivity because they are fixed above the Si–Osix-membered rings. Detailed comparison indicates that Fe-substitution has no significant influence on the pore properties of Plg.