Proteins and protein-like molecules are abundant in various geochemical environments; they form complexes with mineral surfaces and with dissolved organic matter. To evaluate the effect of proteins on rates of dissolution of minerals, experiments on the dissolution of amorphous silica in solutions containing various concentrations of bovine serum albumin (BSA) were performed in this study. The dissolution experiments were carried out by a batch method using solutions of 0.1 mM NaCl with 0.00, 0.05, 0.1, 0.2, 0.5, and 1.0 mg/mL of BSA at three different pH conditions, 6, 5, and 4. The results of the experiments demonstrated that BSA exhibited strong rate-enhancement effects on the dissolution of amorphous silica and were dependent on BSA concentration and the solution pH. At pH 6, the dissolution rates of amorphous silica appeared to increase successively by ~1.6, 2.2, 2.4, 2.5, and 2.9 times with increasing BSA concentrations of 0.05, 0.1, 0.2, 0.5, and 1.0 mg/mL, respectively. The rates of dissolution increased by greater degrees, ~3.1–5.8 and 4.9–13.0 times at pH 5 and 4, respectively. According to the calculated charge distributions of amino acid residues of the BSA molecule, the dissolution rates of amorphous silica were likely to be enhanced by attractive electrostatic interactions of the positively charged side chains of lysine, arginine, and histidine residues with the negatively charged >SiO− sites on the amorphous silica surface. The negatively charged side chains such as glutamic acid and aspartic acid residues may inhibit the attractive interaction, depending on the degree of deprotonation.

During the 1519–1522 Magellan expedition, the astronomer Andrés de San Martín made two remarkably accurate longitude measurements, an order of magnitude better than what was typical for the 16th century. How he managed to do so remained shrouded in mystery for the past 500 years. Using modern ephemerides, we have retraced San Martín's observations and calculated their error signatures, clarifying the method he used (a simplified version of lunar distances) and why two out of his six measurements were accurate (a rather fortuitous cancellation of errors). It would be rash to dismiss San Martín's work as sheer luck though, as he was an exceedingly rare combination of a capable astronomer and a knowledgeable mariner.

Loess is a large-scale deposit which is easy to mine and widely distributed on the epipedon. The clay fraction of loess, also known as ‘loessial clay’, is a very important component of loess which affects its properties and performance. From a ‘materials’ perspective, the clay fraction of loess has been ignored. Recently, loess particles have attracted interest because of their potential applications. The focus in the current review is on the methods of modifying loess particles and their application as functional materials. The major components of loess particles are clays, calcite, and quartz, with the clays including kaolinite, illite, montmorillonite, and chlorite. Loess has a range of particle sizes, types, and dispersibilities. The particles agglomerate readily, mainly because cementation occurs readily in the clay fraction. Loess particles can be modified and their properties can be improved by compaction, separation, purification, acidification, calcination, surfactant modification, geopolymerization, and polymer modification. Loess-based functional materials have been used as sorbents, eco-friendly superabsorbents, soil and water conservation materials, humidity-regulating materials, and building materials. Separated and purified loess particles can adsorb metal ions and harmful elements directly. Surfactant-modified loess particles can remove organic compounds effectively. After modification with polymers, loess particles exhibit greater capacity for the removal of environmental pollutants such as harmful metal ions and dyes. As a superabsorbent, modified loess shows excellent thermal stability and swelling behavior. Calcined loess could be utilized as an energy-saving building material with good humidity-regulating performance, and geological polymerization has further expanded the scope of applications of loess in architecture. In summary, loess-based functional materials, which are inexpensive and ecologically friendly, deserve more attention and further development.

Synthetic siliceous mesoporous materials are of great value in many different applications, including nanotechnology, biotechnology, information technology, and medical fields, but historically the resource materials used in their synthesis have been expensive. Recent efforts have focused on indirect synthesis methods which utilize less expensive silicate minerals as a resource material. The purpose of the present study was to investigate talc, a natural silicate mineral, as one such resource. It was used as raw material to prepare two advanced materials: porous silica (PS) and ordered mesoporous silica (MCM-41). The PS, with a specific surface area of 260 m2/g and bimodal pore-size distribution of 1.2 nm and 3.7 nm, was prepared by grinding and subsequent acid leaching. The MCM-41, with a large surface area of 974 m2/g and a narrow pore-size distribution of 2.8 nm, was obtained using a surfactant, cetyltrimethylammonium bromide (CTAB), by hydrothermal treatment using the as-prepared PS as a source of Si. The two resultant materials were characterized by small angle X-ray diffraction (SAXRD) and wide-angle X-ray diffraction (WAXRD), high-resolution transmission electron microscopy (HRTEM), solid-state magic-angle-spinning nuclear magnetic resonance (MAS NMR), Fourier transform infrared spectroscopy (FTIR), and N2 adsorption-desorption measurements. Based on these measurements, possible processes of transformation of PS from talc, upon acid treatment, and the formation of MCM-41 were investigated systemically. Acid leaching induced the transformation of a rigid layered structure to a nearly amorphous one, with micropores formed by a residual layered structure and mesopores formed from a condensed framework. The MCM-41 was a mixture of silanol groups (Si(SiO)3(OH)) and a condensed Q4 framework structure (Si(SiO)4), with a small amount of remaining Q3 layered structure (Si(SiO)3OMg). The increased Q4/Q3 value confirmed greater polymerization of MCM-41 than of PS. At the low CTAB concentration used (2 wt.%), the highly charged silicate species controlled the surfactant geometry. Charge-density matching, together with the degree of polymerization of the silicates, determined the resultant mesophase.

This article focuses on three of Beat Furrer's works described as opera or music theatre: Begehren (2001), FAMA (2005) and Wüstenbuch (2010). Each of these pieces sets texts from Roman, contemporary and historical authors in exploration of the liminal spaces between life and death, and the possible transitions between them. In Wüstenbuch one such text is included from the Papyrus Berlin 3024, known as the source of the Ancient Egyptian philosophical text ‘The Dispute between a Man and his Ba’, a reflection on the meaning and value of life and the transition between life and death. Furrer's compositional style does not offer a linear narrative on such questions but rather multiple perspectives and tableaux, each of which calls the others and itself into question. In order to explore this and understand what the meeting and interchange of the different texts and authors offers within the context of Furrer's music, I outline a method of ‘listening intertextually’ in order to hear the liminal spaces not only within but between these compositions. I consider the hybrid and hypertexts that arise within the music, and the ways that they can be therefore considered – as in the subtitle often given to FAMA – a ‘drama of listening’.

The chemical and structural properties of Mg smectites in the Vicálvaro sepiolite deposit have been studied in detail. The characterization was performed on different size-fractions of selected smectitic samples (5−2 µm; 2−1 µm; 1−0.5 µm; <0.5 µm and <0.1 µm). The chemical compositions of individual particles (5−1 µm) and of bulk undifferentiated fine fractions (1−<0.1 µm) were determined by energy dispersive spectroscopy-scanning electron microscopy and interpreted with the aid of X-ray diffraction (XRD) and infrared spectroscopy (IR) methods. The XRD and IR data demonstrate that all of the Mg smectite materials studied are mainly composed of a complex mixture of stevensite, saponite and mica-type minerals. Although the presence or absence of saponite cannot be confirmed absolutely, stevensite is a significant component of these Mg smectites. This is proven by the calculated layer charge reduction after the Hofmann-Klemen effect. The results are in close agreement with the suggested mechanism of topotactic overgrowth of stevensite on pre-existing phyllosilicate templates. This characterizes clay diagenesis in saline-lake systems.

Reduced-charge samples were prepared from Li+- and Ni2+-saturated SAz-1 montmorillonite by heating at 150 and 300°C for 24 h. X-ray diffraction analysis showed interstratification of non-swelling and swelling interlayers in LiS150, while fully expandable interlayers were found in NiS150. Heating at 300°C caused collapse of the interlayers in LiS300 in contrast to NiS300, for which some expandable layers were interstratified in the pseudo-pyrophyllite structure. The infrared (IR) spectra of heated Li-SAz showed new OH-stretching and overtone bands near 3670 cm−1 and 7170 cm−1 (1395 nm), respectively, indicating creation of local trioctahedral domains containing Li(I) in the previously vacant octahedra. No evidence of OH groups in trioctahedral coordination was found in the spectra of heated Ni-SAz. Nickel is supposed to be trapped in the hexagonal holes of the tetrahedral sheets. Reduction of the layer charge substantially affected the extent of the dissolution of SAz-1 montmorillonite in HCl. The MIR and NIR spectra of unheated Li- and Ni-SAz showed a substantial degradation of their structure after acid dissolution. New bands observed at 3744 cm−1 and 7314 cm−1 (1367 nm) were assigned to the vibrations of Si-OH groups formed upon acid treatment. These bands are a means of checking the extent of acid attack on smectites, even in cases when no differences are observed in the 1300−400 cm−1 spectral region (traditionally used to monitor this process). Both the IR spectra and solution analysis revealed that development of non-swelling interlayers in heated montmorillonites substantially reduced dissolution of these samples. The results obtained confirmed that acid attack of the smectite structure occurred at both interlayer surfaces and edges. If the accessibility of the layers for protons is low due to non-swelling interlayers, the dissolution was slower and took place mainly from the particle edges.

Crystal truncation rod (CTR) X-ray diffraction is an invaluable tool for measuring mineral surface and adsorbate structures, and has been applied to several environmentally and geochemically important systems. Traditionally, the method has been restricted to single crystals with lateral dimensions >3 mm. Minerals that meet this size criterion represent a minute fraction of those that are relevant to interfacial geochemistry questions, however. Crystal screening, data collection, and CTR measurement methods have been developed for crystals of <0.3 mm in lateral size using the manganese oxide mineral chalcophanite (ZnMn3O7·3H2O) as a case study. This work demonstrates the feasibility of applying the CTR technique to previously inaccessible surfaces, opening up a large suite of candidate substrates for future study.

Mud shale is characterized by low strength and strong swelling, with rheological effects and deformation caused by drilling fluid and formation water. Establishing a rheological model to characterize the deformation characteristics is key to solving the problem of wellbore stability. The influence of moisture content on rock strength and creep mechanical properties were studied by means of water absorption, uniaxial compression, and creep tests. The tests showed that with the increase in moisture content, the elastic modulus and strength of hard brittle mud shale decreased. Further, under the same load, the instantaneous strain increased with increasing moisture content. Meanwhile, under various loading stresses, rock creep exhibited non-linear characteristics, which can be divided into three different creep stages: attenuated creep, stable creep, and accelerated creep. Starting with a non-linear viscous dashpot, and then introducing aging degradation and water-bearing weakening effects, based on the water-bearing creep characteristics of hard brittle shale as well as the modeling ideas of the classic component combination model, a new improved creep model based on the Nishihara model was established to describe the characteristics of the accelerated creep stage of hard brittle mud shale with various moisture contents. Subsequently, the Levenberg–Marquardt non-linear, least-squares method was adopted to invert the creep parameters. The results showed that the simulated creep curves achieved by employing the new creep model were consistent with the experimental results, thereby confirming the ability of the new non-linear creep model to provide a theoretical reference for the study of wellbore stability of hard brittle mud shale.

Sub-micrometer clay particles are of interest in clay-polymer applications, especially when transparency is important. The scattering of light can be reduced by the adjustment of the refractive index (RI) of the clays to that of the matrix. In this study, the RI of sub-micrometer illite particles was changed by treatment with 5 M HCl for treatment times ranging between 2 and 24 h. The dissolution of Fe leads to a decrease in the RI of illite from 1.587 for the unaltered material to 1.502 after 24 h. The layer structure of the illite particles was preserved during the treatment. The RI of the sub-micrometer illite particles was determined by means of a photospectrometer measuring the light intensity passing through suspensions containing the clay particles, with varying refractive indices.

Modified kaolinites possess excellent adsorption properties and, therefore, are regarded widely as potential catalytic components. The use of modified kaolinites as a catalytic component for Fischer–Tropsch synthesis (FTS) has remained unexplored, however. In the current study, delaminated and pit-rich nano-kaolinite was prepared via acid treatment of N-methylformamide (NMF)-intercalated kaolinite (intercalation-etching strategy), and was used as a support to prepare a cobalt-based FTS catalyst (denoted as 15%-Co-HNKln). Compared with other FTS catalysts, the supports for which were raw kaolinite or directly acid-treated kaolinite, the 15%-Co-HNKln showed several advantages such as large specific surface area, dispersed Co particles with small particle size, more new active sites, and significant surface acidity. Given the aforementioned advantages, the 15%-Co-HNKln catalyst demonstrated very good FTS performance. Compared with that of the raw kaolinite-supported FTS catalyst, the CO conversion rate and C5–C12 hydrocarbon selectivity of 15%-Co-HNKln increased by 20% and 15%, respectively.

Kaolin samples from the Jari deposit (Amazon region) were studied using various techniques to characterize its structural and crystallochemical aspects, and to establish its origin and evolution. A profile 60 m thick was selected in a kaolin mine (Morro do Felipe) located at the banks of the Jari river. Despite the great thickness of the deposit and the variety of kaolin types, the mineralogical composition is rather homogeneous and is mainly kaolinite associated with gibbsite and small amounts of quartz, anatase, goethite and hematite. The field observations and the morphological analysis indicate the existence of sedimentary features throughout the whole profile except for the upper aluminous clayey layer (Belterra Clay). This is evidence that the Rio Jari kaolin deposit originated from sedimentary material, the Alter do Chão Formation. The presence of alternating clay and sandy layers is explained by sedimentation processes with great depositional energy variation. Thus, the accumulation of thick clay layers was related to a low-energy phase, and during the high-energy phases, the deposition process led to the accumulation of sandy materials, constituted essentially of quartz and showing strong textural and structural variation. Later on, periods of hydromorphy were responsible for iron removal and consequently for the bleaching of the sedimentary formation. The crystallinity data show an increase of the structural disorder toward the surface associated with an increase in the amount of structural Fe in the kaolinite. The Rio Jari kaolin deposits should be considered as having originated from kaolinitic clay sediments of the Alter do Chão formation (protore) that was submitted to intensive lateritic weathering processes.

Interpreters unanimously read ἐνευλογηθήσονται in Gen 12:3b LXX as a passive. Good evidence, however, exists to challenge and problematize this conclusion. Recent linguistic studies on the ancient Greek middle voice reveal that aorist and future -θη- forms express a semantically middle domain. When we reexamine the word ἐνευλογέομαι within this light, a better option emerges for seeing its -θη- forms as manifestations of speech actions within this middle domain. In their own unique ways, the LXX as well as Philo, Paul, and Acts further corroborate this alternative. As a result, we may read ἐνευλογηθήσονται in Gen 12:3b LXX as a speech action middle: “to pronounce blessings.” The proposed reading promotes a better understanding of Abraham within Genesis LXX. Rather than a means to an end, Abraham remains at the center of God’s blessing as the earth’s families cry out: “God make me like Abraham!”