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Two phyllosilicates (montmorillonite and saponite) have been selected as starting materials to synthesize ZrO2- and Al2O3-pillared clays by the insertion of polyoxocations and subsequent calcination. These pillared clays display higher surface area, porosity and available acid sites in comparison to their respective raw clays. These samples were tested in the one-pot process to transform furfural into obtain valuable products. The incorporation of ZrO2 allows to reach the highest furfural conversion values, with high yields towards furfuryl alcohol (FOL) at shorter reaction times, whereas the formation of i-propyl furfuryl ether (iPFE) is favored at longer times, attaining iPFE yields of about 50% after 24 h at 170 ºC, using isopropanol as sacrificing alcohol. [ABSTRACT FROM AUTHOR]

We studied Caleta el Cobre 022, a nakhlite showing a high abundance of aqueous alteration products, commonly called “iddingsite” and compared it to eight other nakhlites, in order to constrain the composition and the history of the aqueous alteration of nakhlites. Olivine grains in nakhlites display planes of secondary fluid inclusions, composed of pyroxene, magnetite, and a void potentially filled by a fluid. They were formed by a first fluid alteration event, previous to the iddingsite alteration event, probably from a late magmatic fluid circulation. We observed magnetite–pyroxene symplectites in olivine grains in most nakhlites, related to the same fluid‐assisted tardi‐magmatic event as the crystallization of the secondary inclusion planes. Those secondary inclusions and symplectites can be observed at the center of iddingsite veins, inside the most altered nakhlites, and are thus interpreted as being weakness planes, easing the circulation of the fluid forming the iddingsite inside the olivine grains. In every nakhlite, the alteration veins show at least two types of iddingsite: a coarse iddingsite with crystals around 50 nm, up to 200 nm, and a fine iddingsite with a nanocrystalline to amorphous texture with crystalline domains <10 nm. Both iddingsite types are composed mainly of Si, Mg, and Fe, with anticorrelated Si and Fe contents. The coarse iddingsite is composed of a mixture of phyllosilicates, with Fe‐oxyhydroxides and minor siderite, and the fine iddingsite has a composition close to saponite. Organic matter located in coarse iddingsite is detected by Raman spectroscopy in the iddingsite of many nakhlites and was confirmed by the TEM study of NWA 10153. In addition, the TEM study of NWA 10153 displays complex chemical zoning in the fine iddingsite of Mg, Ca, Mn, S, P, and Al, suggesting at least two stages of circulations. Both the compositions and textures of the two types of iddingsite are suggestive of a progressive evolution of the alteration fluid, enriched in elements from basaltic mineral dissolution, with crystallization mainly by filling of existing fractures, and selective dissolution of host olivine. We also observe pyrrhotite–magnetite veinlets at the center of iddingsite veins and cross‐cutting iddingsite veins and silicates, which are interpreted as the result of another later fluid circulation. [ABSTRACT FROM AUTHOR]

Carbonaceous chondrites contain amino acids, with variable abundances and isotope compositions between and within carbonaceous chondrites. The parent body processes, and the presence of clay minerals may explain those differences. Here, we experimentally investigate the evolution of 6 amino acids (glycine, β-alanine, α-alanine, 2-aminoisobutyric acid, γ-aminobutyric acid, and isovaline) exposed to hydrothermal conditions in the presence or absence of silicates. We determined the chemical nature and isotopic composition of the organic compounds of the soluble and solid fractions of the residues using X-ray diffraction, spectroscopy, and mass-spectrometry methods. Glycine and α-alanine exhibit a rather high stability, which is consistent with the measured abundances of α-alanine and glycine in chondrites having experienced various degrees of aqueous alteration. In the meantime, the evolution of β-alanine under hydrothermal conditions leads to the formation of a new compound, which likely results from the decarboxylation and deamination of β-alanine followed by recombination. More than 95 % of γ-ABA was transformed into 2-pyrrolidione though self-cyclization during the aqueous alteration. The solid residues of the experiments conducted in the presence of clay minerals contain organic material, with abundances varying depending on the amino acid used for the experiments (TOC isovaline > 2-aminoisobutyric acid > γ-aminobutyric acid > glycine > α-alanine > β-alanine). Clay minerals thus preferentially trap branched amino acids over chained amino acids, likely within their interlayer spaces as suggested by XRD data. The δ13C values of amino acids have not changed significantly during the experiments, even with the presence of silicates. Thus, the δ13C values of amino acids reported in CR and CM chondrites likely relate to synthetic conditions or the origin of their precursors (i.e. inherited from the pre-accretion processes). [ABSTRACT FROM AUTHOR]

This study presents the synthesis of a CuO-TiO2–saponite ternary nanocomposite via a hydrothermal method, designed to efficiently remove bromocresol green dye. Characterization techniques, including X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy, confirmed significant interactions between metal oxide nanoparticles and the clay mineral matrix. Diffuse reflectance and photoluminescence analyses revealed a narrow band gap and surface defects, such as oxygen vacancies, enhancing the material's photocatalytic properties. Under UV irradiation, the nanocomposite achieved 83% discoloration of bromocresol green dye within 150 min. The inhibitor studies identified hydroxyl and superoxide radicals as key species in the degradation mechanism. This work underscores the potential of clay-mineral-based nanocomposites, where clay minerals function both as structural support and as enhancers of the semiconductor's photocatalytic activity. [ABSTRACT FROM AUTHOR]

Saponite is classified as a trioctahedral mineral of the smectite group.Natural saponite of the Lomonosov deposit (Arkhangelsk region, Russia) is represented as Na- or Ca- forms according to XRD analysis. The interlayer space of the structure contains water molecules. The saponite clay sampled at the deposit is represented by pulp. The clay powder for the research was obtained by the technology of concentrating fine clay material. The crystallochemical formula of saponite was calculated based on the data obtained from XRD, XRF and atomic emission analyses. The purpose of the research was to study the effect of mixed sodium carbonate-sulfate electrolyte (Na2SO4 - 80%; Na2CO3-20%), polyacrylamide (PAA) and low viscosity polyanionic cellulose (PAC L) on the structure, filtration and rheological properties of saponite suspension. The optimum solids content in the water suspension of saponite clay was determined to be in the range of 85-100 g/l. Going out of range leads to deterioration of filtration properties presented by significant increase in filtration loss or increased thickness of the filtration cake. Filtration loss at 85 g/l solids content in the water suspension was 22 cm³/30 min. Addition of mixed sodium carbonate-sulfate electrolyte to the saponite suspension improved rheological properties, but increased filtration loss to 34-36 cm³/30 min. The admixture of polyacrylamide leads rather quickly to flocculation and sedimentation of clay particles; filtration loss was 16-21 cm³/30 min. The presence of polyanionic cellulose in the suspension creates a gel structure, increasing the viscosity of the mud system and significantly reducing filtration loss to 7-9 cm³/30 min. [ABSTRACT FROM AUTHOR]

A new polymer–mineral composite was synthesized by adsorption of the copolymer of 5-(4′-nitro)-phenylazo-8-methacryloxyquinoline with methyl methacrylate on the surface of natural saponite clay. Using computer processing of isotherms of low-temperature adsorption–desorption of nitrogen, a decrease in the specific surface area of saponite after fixing this copolymer was recorded. Using the BJH method, it was calculated that after the adsorption of the copolymer, the average pore volume of the surface of the original mineral decreases and the average pore diameter increases. The sorption capacity of the synthesized composite concerning metal ions compared to the original mineral increases. [ABSTRACT FROM AUTHOR]

This study evaluated non-fibrous Mg-clays as potential adsorbents of emerging contaminants (ECs) from water. The materials were characterized, and their textural and structural properties were related to their ability to remove two model EC molecules: ciprofloxacin (CPX) and lidocaine (LID). The results showed that Ad-6 and Ad-7 are mixed-layer kerolite/stevensite, while Ad-5 and Ad-8 are mainly composed of smectite minerals like stevensite and saponite, respectively. Ad-8 exhibited the highest CPX-adsorption capacity (0.91 mmol·g−1 clay), likely due to its saponite content. Mixed-layer materials also performed well, with Ad-6 and Ad-7 achieving an adsorption capacity of 0.8 and 0.55 mmol·g−1 clay, respectively. Adsorption studies suggested that CPX is adsorbed through ion exchange in materials with high smectite content (Ad-8 and Ad-5), while interstratified materials showed enhanced retention due to kerolite presence, which improves their porous structures. Similar findings were observed for LID, indicating a cationic-exchange mechanism for LID adsorption in all the materials and suggesting that the molecular size of the EC could regulate the removal capacity of these materials. This work showed that the studied Mg-clays could be effectively used for the removal of pharmaceutical pollutants, expanding their commercial possibilities. [ABSTRACT FROM AUTHOR]

The sol–gel process was applied to prepare ZnO-saponite nanocomposite for environmental remediation and investigation of photocatalysis mechanisms. The nanocomposite followed the photodegradation of Rhodamine B (RhB) as a model dye under irradiation with visible light. The materials were characterized by X-ray diffraction, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy, photoluminescence, Point of zero charges (Pcz), and Brunauer–Emmett–Teller (BET). Reuse, the effect of scavengers, and toxicity were also investigated. The results showed an effective incorporation of the semiconductor on the surface of the support, forming a hexagonal structure with the wurtzite phase of ZnO. The evaluation of texture and morphology showed the effective distribution of ZnO nanoparticles on the surface of the synthesized photocatalyst. The intensified adsorption/photocatalysis process using saponite-based nanocomposite achieved more than 85% RhB dye removal efficiency after 270 min. It followed presented pseudo-first-order kinetics with a constant equal to 6.627 × 10–1 min−1. Furthermore, the evaluation of the effect of scavengers indicated that alcohol played an important role in scavenging hydroxyl radicals. It was stable after evaluating the catalyst after successive cycles, maintaining its structure, as FTIR proved. Furthermore, the studied nanocomposites did not show evidence of toxicity, thus being promising candidates for application in the removal of polluting dye. [ABSTRACT FROM AUTHOR]

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Addressing climate change requires transitioning to cleaner energy sources and adopting advanced CO2 capture techniques. Clay minerals are effective in CO2 adsorption due to their regenerative properties. Recent advancements in nanotechnology further improve their efficiency and potential for use in carbon capture and storage. This study examines the CO2 adsorption properties of montmorillonite and saponite, which are subjected to a novel microwave-assisted acid treatment to enhance their adsorption capacity. While montmorillonite shows minimal changes, saponite undergoes significant alterations. Furthermore, the addition of silica pillars to smectites results in a new nanomaterial with a higher surface area (653 m2 g−1), denoted as reversed smectite, with enhanced CO2 adsorption capabilities, potentially useful for electrochemical devices for converting captured CO2 into value-added products. [ABSTRACT FROM AUTHOR]

Samples were recently collected from the carbonaceous asteroid (162173) Ryugu, by the Japan Aerospace Exploration Agency (JAXA) Hayabusa2 mission. They resemble CI chondrites material, thus showing clear evidence of extensive aqueous alteration attested by the widespread presence of a mixture of serpentine and saponite. We present here a scanning transmission electron microscopy study of the Ryugu dominant lithology of the phyllosilicate matrix at the nanometer scale, which we compare with that of the Orgueil CI chondrite. In both objects, the phyllosilicates are of comparable nature and texture, consisting of a mixture of small‐sized crystallites of serpentine and saponite. At the micrometer scale or less, the texture is an alternation of fine and coarse domains. The fine‐grained regions are dominated by saponite. In Ryugu, they enclose numerous Fe,Ni nanosulfides, whereas in Orgueil, S‐ and Ni‐rich ferrihydrite is abundant. The coarse‐grained regions contain more serpentine and no or little Fe,Ni sulfides or ferrihydrite. Scanning transmission x‐ray microscopy at the Fe‐L3 edge also reveals that iron valency of phyllosilicates is higher and more homogeneous in Orgueil (~70% Fe3+) than in Ryugu (<50% Fe3+). We interpret the observed textures as being mostly a consequence of aqueous alteration, likely resulting from the replacement by phyllosilicates of submicrometric components, initially agglomerated by a primary accretion. The fine‐grained domains may result from the replacement of GEMS (GEMS—glass with embedded metal and sulfides) objects or from other types of nanometric assemblages of silicate and Fe‐based nanophases. On the other hand, the coarse‐grained regions may correspond to the replacement of anhydrous crystalline silicates of the olivine and pyroxene type. The major difference is the presence of Fe,Ni sulfides in Ryugu and of ferrihydrite and higher iron valency of phyllosilicates in Orgueil. This might be due to long‐term terrestrial weathering that would have destabilized the nanosulfides. We also explore an alternative scenario involving more oxidizing hydrothermal conditions on the Orgueil parent body. [ABSTRACT FROM AUTHOR]

Samples returned from the carbonaceous asteroid (162173) Ryugu by the Hayabusa2 mission revealed that Ryugu is composed of materials consistent with CI chondrites and some types of space weathering. We report detailed mineralogy of the fine‐grained Ryugu samples allocated to our "Sand" team and report additional space weathering features found on the grains. The dominant mineralogy is composed of a fine‐grained mixture of Mg‐rich saponite and serpentine, magnetite, pyrrhotite, pentlandite, dolomite, and Fe‐bearing magnesite. These grains have mineralogy comparable to that of CI chondrites, showing severe aqueous alteration but lacking ferrihydrite and sulfate. These results are similar to previous works on large Ryugu grains. In addition to the major minerals, we also find many minerals that are rare or have not been reported among CI chondrites. Accessory minerals identified are hydroxyapatite, Mg‐Na phosphate, olivine, low‐Ca pyroxene, Mg‐Al spinel, chromite, manganochromite, eskolaite, ilmenite, cubanite, polydymite, transjordanite, schreibersite, calcite, moissanite, and poorly crystalline phyllosilicate. We also show scanning transmission electron microscope and scanning electron microscope compositional maps and images of some space‐weathered grains and severely heated and melted grains. Although our mineralogical results are consistent with that of millimeter‐sized grains, the fine‐grained fraction is best suited to investigate impact‐induced space weathering. [ABSTRACT FROM AUTHOR]

Due to the growing interest in organic components in cosmetics, there is an increasing interest in using natural materials such as clays. The aim of the study was to provide and compare data on the use of clay as a component in cosmetic products. A literature search was conducted from scientific sources, and data were entered into Microsoft Excel tables for subsequent comparative analysis. Fourteen clay minerals were analyzed -- zinc, hematite, rutile, muscovite, talc, kaolinite, sepiolite, hectorite, montmorillonite, halloysite, saponite, bentonite and palygorskite. Clinoptilolite. All the minerals investigated, except for rutile, zinc, and clinoptilolite, exhibited high sorption capacity. Rutile, clinoptilolite, zinc, and muscovite have large particle sizes, whereas kaolinite, hematite, bentonite, and palygorskite have medium sizes, and sepiolite, saponite, halloysite, hectorite, and montmorillonite have smaller ones. Saponite and palygorskite have significant molecular weight, while zinc, hematite, and rutile have the highest density. Rutile, hematite, clinoptilolite, and zinc have high hardness, whereas talc, halloysite, bentonite, montmorillonite, hectorite, and saponite have lower hardness. Cosmetic clay minerals have similar properties, but to varying degrees and under different conditions, proper application of clays ensures the improvement of cosmetic and therapeutic preparations. [ABSTRACT FROM AUTHOR]

The rheological properties of three Na-activated, trioctahedral Mg-bentonites (hectorite clay from the CMS Source Clay Project repository, saponite clay from Spain and stevensite clay from Rhassoul, Morocco) and a sepiolite clay from Greece were examined after dynamic ageing at temperatures up to 230°C. The 5% w/v suspensions were prepared by dispersing the clay mineral samples in distilled water. The suspensions underwent dynamic, thermal ageing for 16 h before determination of the viscosity, filtration loss, filter cake thickness and pH and the concentration of dissolved Na + and Mg 2+. Thermal ageing contributed to the dispersion of clay particles, with a direct effect on plastic and apparent viscosity, introducing pseudoplastic behaviour. With the exception of the stevensite clay at 230°C that displayed limited dissolution at 230°C and partial conversion to kerolite, the clays were stable at high temperatures. The Na-activation of all clays except for stevensite was not adversely affected by thermal ageing. Thermal ageing of stevensite at 230°C facilitated Na exchange and yielded suspension with high viscosity and low filtrate loss. Only the suspensions of hectorite and those of stevensite aged at 230°C met with American Petroleum Institute specifications. The thermal behaviour and rheological properties of the clays might be interpreted according to the intrinsic properties of the clay minerals, such as layer charge and charge distribution. [ABSTRACT FROM AUTHOR]

The authors justify theoretically and experimentally the promising modification methods for saponite—pillaring and thermal treatment. These methods ensure production of sorbents with high capacity of cation exchange relative to cations of rare earth elements. The mechanism of pillaring and thermal treatment of saponite-bearing products at the temperature of 625 °C includes expansion of the mineral layers, generation of additional acid and oxidation–reduction centers (pillaring), as well as restructuring with formation of meta stable phases (thermal treatment). Optimization of application parameters of the sorbent (pH, sorbent-to-solution ratio) ensures efficient recovery of some REE from pregnant solutions of eudialyte concentrate leaching at the adsorption capacity up to 18.8 mg/g. [ABSTRACT FROM AUTHOR]

The photophysical behaviors of benzimidazolium derivative [4-(1,3-dimethylbenzimidazol-3-imu-2-yl)-N, N-diphenylaniline (2-(4-(diphenylamino)phenyl)-1,3-dimethyl-1H-benzo[d]imidazol-3-ium)] (BID) in water, organic solvents and on synthetic saponite were investigated. The fluorescence quantum yield (Φf) of BID was 0.91 on the saponite surface under the optimal condition, while that in water was 0.010. Such fluorescence enhancement on the inorganic surface is called "surface-fixation induced emission (S-FIE)". This fluorescence enhancement ratio for BID is significantly high compared to that of conventional S-FIE active dyes. From the values of Φf and the excited lifetime, the non-radiative deactivation rate constant (knr) and radiative deactivation rate constant (kf) of BID on the saponite surface and in water were determined. Results showed that the factors for fluorescence enhancement were both the increase of kf and the decrease of knr on the saponite surface; especially, knr decreased by more than two orders due to the effect of nanosheets. The fluorescence quantum yield increased approximately 90 times by the addition of clay. [ABSTRACT FROM AUTHOR]

To improve the adsorption and reusability of polypropylene (PP) fiber membranes, the organically modified saponite (Sap@P(St‐co‐MMA)) was prepared by solution polymerization. Furthermore, PP‐based nanocomposite fiber membranes with strong oil adsorption, thermal stability, and reusability were prepared via melt‐blown technology. The increased specific surface area of PP‐based nanocomposite fiber membranes (PP‐1.5%) provided more active sites for the oil adsorption. Simultaneous rheology and Fourier transform infrared measurements tests showed that Sap@P(St‐co‐MMA) enhanced the crystallinity of PP matrix, promoted the regular arrangement of molecules, and improved the intermolecular interaction force, which was beneficial for the oil adsorption. The adsorption of PP‐1.5% (1.5 wt% addition of Sap@P(St‐co‐MMA)) fiber membrane for xylene and kerosene reached a maximum of 15.84 and 22.84 g g−1, respectively. In the treatment of coal tar wastewater, the removal rate of oil can reach 62.9%, and the removal rate can still reach 51.17% after five cycles of experiments. In summary, PP‐1.5% fiber membrane does not produce secondary pollution to the environment, and is a kind of oil removal material with good application prospect. Highlights: PP‐based nanocomposites fiber membrane with strong oil adsorption was prepared.Organically modified saponite had strong heterogenous nucleation for PP matrix.Sap@P(St‐co‐MMA) increased the specific surface area of PP‐based fiber membrane. [ABSTRACT FROM AUTHOR]

Five phyllosilicates (kaolinite, montmorillonite, saponite, sepiolite and palygorskite) have been selected as starting materials for the synthesis of zeolites. Among them, kaolinite and montmorillonite display the lowest Si/Al molar ratio leading to aluminosilicates with high crystallinity. Thus, the hydrothermal treatment under basic conditions forms 4A zeolite when kaolinite is used as starting material while 13X zeolite is obtained when montmorillonite is used as starting material. The microporosity and CO2-adsorption capacity of the prepared zeolites are directly related to its crystallinity. Thus, in order to improve it, raw phyllosilicates were subjected to a microwave-assisted treatment to remove undesired Mg or Fe-species, which have a negative effect in the assembling of the zeolites by hydrothermal basic conditions in a second step. The highest adsorption value was 3.85 mmol/g at 25 °C and 760 mm of Hg for Mont-A-B sample after the consecutive treatments. [ABSTRACT FROM AUTHOR]

Carbon foams with and without functional particles were prepared via a simple direct foaming process. The carbon foams were composed of pyrolytic carbon and graphite. In the foams with additional functional particles, the latter were integrated directly in the direct foaming process. These functional particles were the catalytic material Saponite and the induction heat‐able material MagSilica®. The foams were characterized including the induction heatability. The foams were also successfully tested in an induction heated lab‐scale reactor for a case study reaction, ethanol to 1,3‐butadiene. [ABSTRACT FROM AUTHOR]

This study investigates the catalytic conversion of ethanol using a modified saponite in both an ohmic and a conventional reactor. For testing in the ohmic reactor the catalyst is stacked in between conductive graphite fleece or formed to conductive pellets. The influence on catalytic activity and axial temperature profiles was examined. Catalytic tests in the ohmic reactor showed comparable results to the conventional reactor. Additionally heating profiles of different conductive materials where taken, within uniform heating was reached with the carbon fleeces. [ABSTRACT FROM AUTHOR]

In this study, solid waste clays from the Emet Concentrator Plant were used. With the data obtained from the characterization tests, it was decided to work with the sample fraction with a Li grade in the range of 1942-2035 ppm, which is below 0.5 mm grain size. Clay samples and salt mixtures are blended at different rates. In the first stage, the leaching effect of salt type and ratio was investigated, and in the second stage, the roasting time and temperature were investigated. The effectiveness of the parameters used in the roasting study was evaluated by lithium extraction studies. In the third phase of the study, leaching, the study was completed by considering the H2SO4 concentration and leaching time. With the processes carried out, first of all, the mixture obtained by blending the sample/salt mixture ratio of 1/1 and between the salts in the ratios of NaCl (0.6)-CaCl2 (0.4); Result of roasting at 900 °C for 1 hour, a roasting efficiency of 77.26% Li was obtained. Then, by leaching the roasted material in the presence of 0.4M H2SO4 for 1 hour, the leaching efficiency was determined to be 89.61% Li. [ABSTRACT FROM AUTHOR]

Here we propose to investigate Ni-functionalized saponite (smectite group) as a viable alternative for low cost H 2 storage for land-based applications. The precursor gel used for saponite synthesis is also tested with respect to its H 2 adsorption properties. Adsorption isotherms recorded at 77 K and 1 bar, 298 K and 120 bar indicate that nickel functionalization does not induce a clear structural or chemical control on the adsorption process. However, Ni-pillared saponites outgassed at 70 °C display a four-time enhanced H 2 uptake (up to 0.12 wt% at 77 K and 1 bar) compared to its counterpart outgassed at 150 °C. Another important finding of this study is the surprisingly high H 2 uptakes of the gel (nano-crystallized) precursor, used for the synthesis of saponite samples (up to 0.19 wt% at 77 K and 1 bar, and up to 0.12 wt% at 298 K and 120 bar). • Nickel functionalization does not induce a clear structural or chemical control on the adsorption process. • Ni-pillared saponites outgassed at 70 °C display a four-time enhanced H 2 uptake (up to 0.12 wt% at 77 K and 1 bar). • Surprisingly high H 2 uptakes of the nano-crystallized gel used for saponite synthesis (up to 0.12 wt% at 298 K and 120 bar). [ABSTRACT FROM AUTHOR]

Simple Summary: The use of various fermentation modifiers in ruminant diets is one of the best strategies for regulating greenhouse gas emissions, primarily carbon dioxide and methane (CH4). Feeding complex mineral substances of natural origin can provide a quick and safe result. Our in vitro studies confirmed these expectations, and saponite clay, due to its high adsorption properties, significantly reduced the production of CH4 and other gases. Reducing the emission of global warming gases currently remains one of the strategic tasks. Therefore, the objective of our work was to determine the effect of saponite clay on fermentation in the rumen of cows. The pH, total gas production, CH4, and volatile fatty acid (VFA) production in ruminal fluid was determined in vitro. Saponite clay from the Tashkiv deposit (Ukraine) has a high content of silicon, iron, aluminum, and magnesium. The addition of 0.15 and 0.25 g of saponite clay to the incubated mixture did not change the pH but reduced the total production (19% and 31%, respectively) and CH4 (24% and 46%, respectively) in the ruminal fluid compared to the control group and had no significant effect on the total VFA levels, but propionic acid increased by 15% and 21% and butyric acid decreased by 39% and 32%, respectively. We observed a decrease in the fermentation rates, with a simultaneous increase in the P:B ratio and an increase in the fermentation efficiency (FE) in the groups fermented with saponite clay, probably a consequence of the high efficiency in the breakdown of starch in the rumen. Therefore, further in vivo studies to determine the effective dose and effect of saponite clay on cow productivity and the reduction of gas emissions are promising and important. [ABSTRACT FROM AUTHOR]

The giant Pre-salt reservoirs represent most of the oil production in Brazil. The main Aptian sag reservoirs were deposited in a unique and highly complex hyper-alkaline lacustrine setting. These deposits are essentially constituted by fascicular and spherulitic calcite precipitated in a magnesian clay matrix (stevensite, kerolite, and saponite/hectorite). Although vital for understanding the origin and main reservoir quality control, the genesis and interactions of clays and carbonates are still poorly constrained. The detailed petrographic description was focused on 812 thin sections from five wells drilled in the Santos Basin Aptian Barra Velha Formation, combined with cathodoluminescence, UV epifluorescence, and X-ray diffraction analyses. The main syngenetic processes were the deposition of finely laminated peloidal and ooidal Mg-clays, the formation of fascicular calcite crusts on the sediment–water interface, and the redeposition of these materials as intraclasts. Abundant clay peloids engulfed in syngenetic shrubs indicate that calcite and clay precipitation was concomitant, though with highly variable rates. Eodiagenetic phases include matrix-replacive and -displacive spherulites and fascicular shrubs; matrix-replacive blocky calcite and dolomite; lamellar carbonates filling matrix shrinkage pores; and microcrystalline calcite, dolomite, and silica replacing the Mg-clay matrix. The preferential dolomitization and calcitization of peloidal layers were most likely due to their higher permeability and larger specific surface. Matrix-replacive saddle dolomite, macrocrystalline calcite, and dawsonite are interpreted as mesodiagenetic or hydrothermal phases after significant matrix dissolution. Unraveling the processes of the formation and alteration of the carbonates and clays and their interactions in the Pre-salt deposits is essential for constraining the depositional and diagenetic conditions in their unique environments and their diagenetic overprinting and for decreasing the exploration risks and increasing the production of those extraordinary reservoirs. [ABSTRACT FROM AUTHOR]

Smectite growth is of importance across various fields due to its abundance on the surface of both Earth and Mars. However, the impact of the crystallinity of initial materials on smectite growth processes remains poorly understood. In this study, the kinetic processes of smectite growth were examined via experimental synthesis of trioctahedral Mg-Ni saponites. Mg-Ni saponites were synthesized using mixed precursors, specifically end-member Mg-saponite and Ni-saponite, which exhibit different crystallinities. The crystal chemistry and morphology of samples were analyzed using X-ray diffraction, Fourier-transform infrared spectroscopy, and high-angle annular dark-field scanning transmission electron microscopy. The experimental results converge towards these main conclusions: (i) the formation of Mg-Ni saponite solid solutions are promoted when the precursors are small particles, whereas large-particle precursors limit their own dissolution and do not yield Mg-Ni saponite solid solutions under the experimental conditions; (ii) because Ni exhibits a greater stability within the saponite structure compared to Mg, the Mg-Ni-saponite solid solutions formed more easily from the mixture of Ni-saponite germs and well-crystallized Mg-saponite precursors than from the mixture of Mg-saponite germs and well-crystallized Ni-saponite precursors; (iii) the dissolution extent (DE) of precursor mixtures increases with longer synthesis time, higher synthesis temperature, and larger gap between synthesis temperature of precursors and of samples, and stabilizes once it reaches a certain value. Thus DE can be used to estimate the kinetics of Mg-Ni saponite crystallization from precursor mixtures. These results obtained from the experimental Mg-Ni saponite system are useful for predicting the evolution processes of smectite in natural systems. [ABSTRACT FROM AUTHOR]

The four smectite clays in the CSSJ reference samples have been examined using TEM/STEM imaging and energy dispersive X-ray spectroscopy (EDS) in SEM and STEM, to characterize their chemical compositions, grain sizes, impurity minerals, and other properties. Fine calcite particles were commonly found along with quartz in the Tsukinuno samples (JCSS-3101, 3101b), which serve as the primary source of calcium as reported in previous bulk analyses. Cristobalite, quartz, and feldspar are prevalent impurity minerals in the Mikawa sample (JCSS-3102), and the STEM-EDS analysis revealed that the composition of the smectite clay is definitely montmorillonite with subtle difference from the Tsukinuno montmorillonite. The synthetic saponite (JCSS-3501) displayed a wide range of crystal sizes. Sulfate and sodium ions are concentrated in the aggregates of very fine saponite crystallites compared to the saponite particles with larger sizes. [ABSTRACT FROM AUTHOR]

In this work, modified saponite (SAP‐g‐PS) was prepared by Pickering emulsion polymerization, and the optimum synthesis conditions of SAP‐g‐PS were investigated. Furthermore, SAP‐g‐PS was used as a reinforcing filler for poly (lactic acid) (PLA) and the mechanical properties results revealed that the elongation at break increased by 81.51% compared to pure PLA when SAP‐g‐PS was added up to 0.5 wt%. Scanning electron microscopy analysis showed that the fracture of PLA based nanocomposite films was ductile. The thermal analysis results showed that the maximum thermal decomposition temperature was increased from 352.19°C (PLA0, pure PLA film) to 361.63°C (PLA3, 0.5 wt% SAP‐g‐PS), and the crystallinity was increased from 18.2% (PLA0) to 31.3% (PLA3) at the traction ratio of 14. The stretch‐induced crystallization behavior of PLA based nanocomposites films was investigated under the conditions of the optimum blow molding process, and it was found that the elongation at break of PLA0 films increased from 25.8% to 37.4% and that of PLA3 was increased from 81.4% to 135.5% with the increase of the traction ratio, the crystallinity of both films showed an increasing trend, which indicated that the presence of the tensile flow field improved the orientation of the PLA, and increased its crystallization and mechanical properties. The thermo‐oxidative aging kinetics of PLA based nanocomposites films with different additions of SAP‐g‐PS were investigated by thermo‐oxidative aging experiments, and the lifetime of the films were predicted by the Arrhenius equation, which showed that the addition of SAP‐g‐PS effectively improved the lifetime of PLA based nanocomposites films. [ABSTRACT FROM AUTHOR]

The authors provide the theoretical and experimental justification for the effective methods of modification of saponite—pillaring and thermal treatment—which ensure production of sorbents possessing high cation exchange capacity relative to cations of heavy metals. The mechanism of pillaring and thermal modification of a saponite-containing product at the temperature of 625 °C involves expansion of layers of the mineral, formation of additional acid or redox sites (pillaring) and restructuring with generation of metastable phases (thermal treatment). Modification of saponite increases static exchange capacity relative to copper cations by 2 times after pillaring and by 2.6 times after thermal treatment. [ABSTRACT FROM AUTHOR]

We provide new support for habitable microenvironments in the near-subsurface of Mars, hosted in Fe- and Mg-rich rock units, and present a list of minerals that can serve as indicators of specific water–rock reactions in recent geologic paleohabitats for follow-on study. We modeled, using a thermodynamic basis without selective phase suppression, the reactions of published Martian meteorites and Jezero Crater igneous rock compositions and reasonable planetary waters (saline, alkaline waters) using Geochemist's Workbench Ver. 12.0. Solid-phase inputs were meteorite compositions for ALH 77005, Nakhla, and Chassigny, and two rock units from the Mars 2020 Perseverance rover sites, Máaz and Séítah. Six plausible Martian groundwater types [NaClO4, Mg(ClO4)2, Ca(ClO4)2, Mg-Na2(ClO4)2, Ca-Na2(ClO4)2, Mg-Ca(ClO4)2] and a unique Mars soil-water analog solution (dilute saline solution) named "Rosy Red", related to the Phoenix Lander mission, were the aqueous-phase inputs. Geophysical conditions were tuned to near-subsurface Mars (100 °C or 373.15 K, associated with residual heat from a magmatic system, impact event, or a concentration of radionuclides, and 101.3 kPa, similar to <10 m depth). Mineral products were dominated by phyllosilicates such as serpentine-group minerals in most reaction paths, but differed in some important indicator minerals. Modeled products varied in physicochemical properties (pH, Eh, conductivity), major ion activities, and related gas fugacities, with different ecological implications. The microbial habitability of pore spaces in subsurface groundwater percolation systems was interrogated at equilibrium in a thermodynamic framework, based on Gibbs Free Energy Minimization. Models run with the Chassigny meteorite produced the overall highest H2 fugacity. Models reliant on the Rosy Red soil-water analog produced the highest sustained CH4 fugacity (maximum values observed for reactant ALH 77005). In general, Chassigny meteorite protoliths produced the best yield regarding Gibbs Free Energy, from an astrobiological perspective. Occurrences of serpentine and saponite across models are key: these minerals have been observed using CRISM spectral data, and their formation via serpentinization would be consistent with geologically recent-past H2 and CH4 production and sustained energy sources for microbial life. We list index minerals to be used as diagnostic for paleo water–rock models that could have supported geologically recent-past microbial activity, and suggest their application as criteria for future astrobiology study-site selections. [ABSTRACT FROM AUTHOR]

The new polymer–mineral composite materials have been obtained by in situ immobilization of poly-[5-(p-nitrophenylazo)-8-methacryloxyquinoline] on the saponite of Tashkivsky deposit (Sap-AzoQN) and clinoptilolite of the Tushinsky deposit (Clin-AzoQN) surface. The fact of polymer immobilization on the surface of minerals by the selected method was confirmed by thermogravimetric analysis combined with mass spectrometry and IR spectroscopy. Scanning electron microscopy showed that the immobilized polymer is located on the surface of both minerals in the form of needles, located in different directions to the surface, and acicular formations. The properties of the composite materials have been determined by means of a sorption test when removing ions Pb2+, Fe3+, and Cu2+ from the model solutions in static conditions. A twofold increase in the sorption capacity of the Sap-AzoQN composite for Cu(II) and Pb(II) ions and a 5.6-fold increase in the Clin-AzoQN composite for Fe(III) ions were recorded compared to the original minerals. As a result, composite materials revealed high-efficiency sorption of heavy metals. [ABSTRACT FROM AUTHOR]

Çok karmaşık bir proses gerektirmeyen kolemanit zenginleştirme tesislerinden, üretim esnasında ve sonunda büyük potansiyel kaynak oluşturan kil içerikli atıklar çıkmaktadır. Bu çalışmada, Eti Maden Emet Bor İşletmesi Hisarcık kolemanit zenginleştirme tesisi katı atık killerinden alınan örneklerin kimyasal içerikleri incelenmiş ve mevcut kilin yapısal formülü tespit edilmiştir. 45 mikron tane boyutu altında kil içerikli atık %12,42 Mg ve 2352 ppm Li tenörüne sahiptir. Mg'ca zengin Li'lu bir simektit (saponit) olarak bilinen kilin su tutucu olma niteliği nedeniyle de kolemanit zenginleştirme prosesinde cevherden kilin uzaklaştırılmasını zorlaştırmaktadır. Yapılan kil ayırma çalışması sonuçları değerlendirildiğinde, elde edilen saf kilin %46,82 SiO2 ve %19,67 MgO tenörleri ile oldukça yüksek içeriğe sahip olmasının yanısıra 1776 ppm Sr, 3057 ppm As ve 2239 ppm Li tenörleri ile değeri daha da artmaktadır. Kil içerikli katı atığın saponit olması ve lityum içermesi endüstriyel kıymetini daha da arttırmaktadır. Kil içerikli katı atıkların, uygun strateji ve değerlendirme yöntemleriyle cevherden ayrılması ve ekonomiye kazandırılmasının önem taşıdığı belirlenmiştir.

The CY chondrites are a group of thermally metamorphosed carbonaceous chondrites. Although they share similarities with the CM and CI chondrites, their primary properties argue for a distinct classification. Previous studies have highlighted their isotopically heavy bulk compositions (δ17O = 10 ‰, δ18O = 21 ‰, Δ17O = 0 ‰) and exceptionally high sulphide abundances (10–30 vol%). In this work we explore their petrography and alteration history. The CYs accreted low abundances of chondrules (15–20 area%) with average apparent diameters slightly larger (∼320–340 µm) than the CM chondrites. In contrast to the CMs, the CYs record an early episode of brecciation prior to the main window of aqueous alteration. Subsequent fluid activity produced a range of alteration extents with both CY2 and CY1 chondrites documented. Phyllosilicate minerals in the CYs were a mix of serpentine and saponite (including occurrences of Na-saponite) with minor quantities of chlorite (within chondrules). An initial generation of Fe-sulphides formed by sulfidation of metal, and by precipitation from S-rich fluids. Three generations of carbonates are recognized, an early generation that infilled voids left by brecciation and co-precipitated with sulphide, a later generation that co-precipitated with magnetite and a final Fe-Mg-bearing generation which formed large (>100 µm) clasts. Only the first-generation carbonates are found in the CY2s, while the CY1s preserve all three generations. Phosphates occur as Ca-apatite or rarely as Mg-bearing apatite and have hydroxylapatite compositions, indicating low halogen activities in the alteration fluids. Refractory oxides (ilmenite and Cr-spinel) occur as precipitates adhering to the margins of phyllosilicates. They formed late in the alteration sequence and attest to oxidizing conditions. During the late-stages of aqueous alteration Fe-sulphides were replaced by magnetite. Thermal metamorphism (Stage II-IV: ∼300–750 °C) overprinted aqueous alteration leading to dehydration and recrystallization of the phyllosilicate matrix and the decomposition of some carbonate phases. Most Fe-sulphide grains survived heating without decomposition as initial partial decomposition from pyrrhotite to troilite under closed system conditions led to elevated ƒS 2 gas and resulted in a stabilizing effect. Retrograde reactions between trapped S 2 gas and metal/magnetite formed a final generation of Fe-sulphides. The survival of Fe-sulphides and their stochiometric troilite compositions are evidence for near-closed system heating. Analysis of organic matter by Raman spectroscopy supports an interpretation of short-duration heating (on the scale of minutes to days), at peak temperatures between 750 and 900 °C. Thus, an impact event was the most likely cause of metamorphic heating. [ABSTRACT FROM AUTHOR]

Human activities have significantly impacted the environment, resulting in a need to restore degraded areas through various remediation techniques. This study aimed to evaluate the effectiveness of saponite in the aided phytostabilisation technique for heavy-metal-contaminated soil. The research was conducted on soil from a post-industrial site characterised by high metal content (Cu, Ni, Cd, Pb, Zn, and Cr) surpassing the established regulatory limits. Saponite was added to the contaminated soil at a ratio of 3% (w/w). The experiment was performed using Lolium perenne L. and Festuca rubra L. due to their adaptability to harsh soil conditions and rapid growth. The results demonstrated that saponite application significantly increased soil pH, which is beneficial for phytostabilisation of heavy metals. Saponite has been found to selectively enhance Ni accumulation in roots while not affecting Pb accumulation in above-ground parts, implying that saponite can effectively regulate heavy metal accumulation in plant biomass. Furthermore, saponite has been observed to significantly decrease soil Cd, Zn, and Cr levels with no impact on Cu, Ni, and Pb levels. Overall, saponite shows promise as an effective and scalable solution for large-scale phytostabilisation projects, contributing to the restoration of degraded soils and the protection of environmental and human health. [ABSTRACT FROM AUTHOR]

Trade balances of fertilizers have been studied in this article. The war's repercussions for the world economy are changes in food, energy, fertilizer prices, and supplies. The production of grain crops in Ukraine and other countries should be increased due to innovative sustainable agriculture technologies that decrease nitrogen granules dissolution. The fertilizers with the controlled release of nutrient elements could increase retention time and improve fertilizer efficiency. This article compared three types of fertilizers with carbamide core and phosphate shell, including various additives (biochar, diatomite, saponite) by morphology end elemental analysis. TEM investigated fertilizer structures in water suspensions to compare their behavior in conditions close to fertilizers dissolution underwater treatment in the soil. The ability to form colloidal micelles was investigated by electrophoreses and compared to find more suitable fertilizer with additives to phosphate shells to slow the release of components and application in agriculture. The surface morphology and internal structure of the granule were investigated by SEM analysis. The elements' distribution in the shell, interface, and core was investigated by EDX spectroscopy. The existence of colloidal micelles due to fertilizers dissolution is essential for decreasing the solubility of fertilizers. It is shown that adding biochar to granule shell increases shell porosity. The uniform nanoporous structure is observed through all thicknesses of the shell that provide moisture penetration through the shell. The fertilizers' porous shell structure and biochar additives' basic pH can reduce soil acidity and nutrient leaching. The colloidal system of biochar-added sample filtrate could contain nanoparticles with 5–15 nm size. It was concluded that the positively charged colloidal micelles are formed for fertilizer samples with biochar and humates addition. For fertilizers, samples with the addition of diatomite and saponite micelles were not formed. [ABSTRACT FROM AUTHOR]

In this paper, Magnetite/Saponite (Fe 3 O 4 /Sap) composites were prepared by hydrothermal synthesis and co-precipitation. The prepared Fe 3 O 4 /sap composites had high purity and good crystallinity, and nano-Fe 3 O 4 was uniformly dispersed on the surface of saponite. Moreover, the removal efficiency of Fe 3 O 4 /Sap composites for Cr (VI) in water was evaluated. This study revealed the existence of abundant oxygen vacancies and hydroxyl groups on the surface of Saponite. During the synthesis of Fe 3 O 4 on the surface of Sap, the multi-directional crystallization can be controlled to increase the reaction activity of the system. Besides, the prepared Fe 3 O 4 /Sap composites provided more reactive edges compared to Fe 3 O 4 in the process of removing Cr (VI). The removal amount of Cr (VI) was found to be 17.95 ​mg/g. The successful preparation of the Fe 3 O 4 /Sap composites and the revelation of the Cr (VI) adsorption mechanism are of great significance for the efficient and green removal of heavy metal pollutants in sewage. [ABSTRACT FROM AUTHOR]

Smectitic clay minerals are unique indicators of paleoenvironmental conditions and exhibit a unique reactivity in the mineral world. Smectites may exhibit tetrahedral substitutions (Al3+, and sometimes Fe3+, can substitute for Si4+ in tetrahedral sites), resulting in a layer-charge increase, thereby impacting their properties (e.g. swelling and sorption capacities, catalytic properties, expandable abilities). The objective of the present study was to determine the influence of pH conditions on the hydrothermal production of smectite end-members exhibiting tetrahedral Al substitutions (saponite, beidellite, and nontronite), using X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) methods. The results of a series of syntheses conducted at various pH values allowed discussion of the crystallization pathways of these smectites from a mechanistic point of view. Altogether, the present study provided easily reproducible protocols for the hydrothermal production of pure saponite, nontronite, or beidellite (i.e. with no other mineral). The successful synthesis of pure saponite was achieved by exposing the starting gels to 230°C for 4 days in solutions at pH ranging from 5.5 to 14. The successful synthesis of pure beidellite was achieved by exposing the starting gels to 230°C for 9 days in a solution at pH 12. The successful synthesis of pure nontronite was achieved by exposing the starting gels to 150°C for 2.5 days in a solution at pH 12.5. Although extrapolating experimental results to natural settings remains difficult, the results of the present study may be of great help to constrain better the geochemical conditions existing or having existed on extraterrestrial planetary bodies. [ABSTRACT FROM AUTHOR]

Alteration minerals in one of the Martian meteorite nakhlites, Yamato (Y) 000802, were studied to understand the alteration process and conditions. Mn‐precipitates are discovered between altered plagioclase grains in Y 000802. Mn‐precipitates consist of hausmannite (Mn2+Mn3+2O4 ${\text{Mn}}^{2+}{{\text{Mn}}^{3+}}_{2}{\mathrm{O}}_{4}$), manganite (γ‐Mn3+OOH), rhodochrosite (Mn2+CO3), and a trace amount of Mn4+O2 mineral. Jarosite KFe3+3SO42(OH)6 $\left({{\text{KFe}}^{3+}}_{3}{\left({\text{SO}}_{4}\right)}_{2}{(\text{OH})}_{6}\right.$) is also found. Mn2+ dissolved from olivine contributes to the formation of Mn‐precipitates. A weakly acidic‐neutral fluid containing a trace amount of CO32− ${{\text{CO}}_{3}}^{2-}$ altered the olivine, and Mn2+ was dissolved into the fluid. The fluid also reacted with plagioclase and probably induced dealkalization of plagioclase, causing a local strong alkaline environment. Plagioclase was altered to ferroan saponite‐nontronite + amorphous SiO2 under alkaline conditions. Simultaneously, Mn2+/3+‐precipitates were formed from the Mn2+‐containing fluid in the interstices between the altered plagioclase grains under the strong alkaline reducing environment. These alterations occurred in the deep part of the nakhlite body, where they are isolated from Martian subsurface water, including strong oxidants. The formation of Mn2+/3+‐precipitates may have been triggered by the melting of permafrost caused by an impact event around ∼633 Ma. Later, the nakhlite body was probably excavated by another impact, making it susceptible to water including strong oxidants. Pyrrhotite was dissolved and a highly acidic oxidizing fluid was formed, which would induce the formation of jarosite and the Mn4+O2 mineral between ∼633 Ma and ∼11 Ma. Plain Language Summary: Manganese‐precipitates and sulfate mineral (jarosite) are discovered in a Martian nakhlites meteorite, Yamato (Y) 000802. In Y 000802, manganese is leached from olivine and precipitates as divalent and trivalent manganese minerals. Manganese‐precipitates are also found at the Endeavour and Gale craters on Mars, which is predicted to be a tetravalent manganese mineral. A strong oxidizing agent is required to form the tetravalent manganese mineral and jarosite. In contrast, a strong alkaline reducing environment is required to form the divalent and trivalent manganese minerals. Hence, Y 000802 would be altered in a deep part of the Martian subsurface where it is isolated from water containing strong oxidizing agents. A trace amount of tetravalent manganese minerals is also found in Y 000802. After the formation of divalent and trivalent manganese minerals, Y 000802 was probably brought to a shallow part of the Martian subsurface by impact, making it susceptible to water containing strong oxidizing agents. The pyrrhotite included in Y 000802 was dissolved by the water, producing a highly acidic fluid that induced the formation of jarosite and tetravalent manganese. These alterations that formed the manganese precipitates and jarosite probably occurred during middle to late Amazonian time. Key Points: Mn2+/3+‐precipitates: hausmannite, manganite, rhodochrosite, and a trace amount of Mn4+O2 mineral were discovered in Y 000802 nakhlitesMn2+/3+‐minerals were precipitated from strong alkaline reducing fluid at the deep part of the Martian subsurfaceLater, Mn4+O2 mineral and jarosite were formed in the nakhlite by strong oxidizing agent near the Martian surface [ABSTRACT FROM AUTHOR]

There is no doubt in the fact that preparations containing Trichoderma as the main component are currently a real alternative to synthetic agrochemicals as antagonists of soil-borne plant diseases and growth stimulators. The use of this kind of drugs does not always give sufficiently stable results. In addition, technological problems can often arise, which are associated with the short shelf life of liquid preparations based on Trichoderma. The use of the solid form of the drug often causes the problem of self-inhibition of conidia germination. And therefore a more careful calculation of the optimal dose for each specific strain is required. The development of multifunctional bio-preparations that are more stable in their effectiveness, especially preparations that include Trichoderma, is one of the most important tasks in the system of biotechnology development, which determined the relevance of the research. The aim of the work is to establish the optimal carrier for the immobilization of Trichoderma viride cells and the effect of immobilization on the stability of drugs. It has been experimentally established that the growth and development of the immobilized fungus Trichoderma viride is influenced by the nature and method of modification of the carrier. It was established that when the fungus immobilized on native and modified carriers (particle size 0.5 μm – 2.5 mm) was seeded on a sterile nutrient medium, a decrease in the growth rate of Trichoderma viride was found, compared to the control one where the native fungus was used. It has been proven that the optimal amount of grinding of both native and modified media is – 150 μm – 1.5 mm. It has been found that saponite modified with starch is the optimal carrier for Trichoderma viride immobilization. It has been proven that upon immobilization of the fungus Trichoderma viride, the latter becomes more resistant to the negative factors of the growth environment (antagonistic action of the natural conglomerate of microorganisms residing on spoiled alfalfa hay).

Clays are fine‐grained rocks that form in the presence of water. Their occurrence typically depends on a combination of geological setting and geochemical conditions. The widespread and diverse clay deposits identified on Mars indicate that the planet experienced multiple episodes of water activity, especially in the early period. The characterisation of Martian clays will reveal key information on geological history, the past climatic conditions and the overall habitability of Mars. Among the analytical techniques typically utilised for such mineralogical characterisation, Raman spectroscopy will be applied for the first time during several robotic exploration missions of Mars in the 2020s. In this study, various clay‐rich samples from Westerwald, Germany were analysed to help inform mission operations and interpretation of data returned by the miniaturised Raman instruments. The samples, as verified by infrared spectroscopy, constitute kaolinites, Al‐rich smectites and Fe/Mg‐rich smectites, which are relevant to the clay mineralogy expected at Martian landing sites (Jezero crater and Oxia Planum). Despite the levels of fluorescence experienced during Raman measurements of the clay‐rich powder samples when using a 532 nm laser, the Raman signatures of phyllosilicates were identified for kaolinite and several different types of smectite (e.g. montmorillonite, nontronite, saponite) in these complex dispersions. Following these measurements, identification of various accessory minerals disseminated in the clay matrix was also achieved using the micro‐Raman system. Finally, a brief discussion concerning the analytical strategies for successful clay analyses using miniaturised Raman instruments is provided. [ABSTRACT FROM AUTHOR]

Pig farming is one of the most productive and early maturing branches of animal husbandry, which plays an important role in the meat balance of the state. Simultaneously with the production of the main products a significant amount of by-products of animal origin accumulates. A large number of pollutants of various origins are released into the atmosphere during the decomposition, including greenhouse gases, which causes pollution of the soil, surface and underground waters. Therefore, the basis of the planned research was to find out the emission of the greenhouse gases from the pig manure under the influence of different doses of inorganic substances (natural sorbents). According to the results of the conducted research, it was established that the level of release of the studied gases -- methane (CH4), carbon dioxide (CO2) and nitrogen oxide (NO) from the pig manure (in vitro) when using different doses of natural sorbents -- vermiculite and saponite with a simultaneous shift of the pH to the acidic side respectively, was 5.31 and 5.67, against 6.2-6.5 in the control. In a comparative assessment of the effect of the investigated sorbents on the emission of greenhouse gases from the pig manure, it should be noted that the level of release of CH4 from the substrate in the variants with vermiculite decreases to 18.6%, CO2 to 37.5%, and NO to 25.7%, and with saponite, respectively up to 7.2%, 20.2 and 22.3%. Therefore, the obtained data indicates the expediency of the usage of the studied sorbents, in particular vermiculite, to reduce the emission of greenhouse gases during the storage of the manure in the storage facilities (lagoons) and directly in the premises, which will make it possible to minimize the negative impact of intensive pig farming on the state of the environment. [ABSTRACT FROM AUTHOR]

Chromotropism in clay-polymer nanocomposite consisted of synthetic saponite, poly-N-isopropylacrylamide (PNIPAAm), and 3,3′,5,5′-tetramethylbenzidine (TMB) was investigated by diffuse reflectance spectroscopy for dry powder specimens and UV-visible absorption spectroscopy for gel specimens. TMB was introduced in the photopolymerized saponite-PNIPAAm via a commonly used cation exchange method. The nanocomposites showed yellow color attributed to TMB radical in dry state but it turned to green by partial formation of blue charge-transfer complex in contacting to water, methanol, and acetonitrile vapor or liquid. The color change was particularly pronounced for acetonitrile and was evident even in a 10% aqueous solution for hydrogels. [ABSTRACT FROM AUTHOR]

Copyright of Boletin de Geologia is the property of Universidad Industrial de Santander and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering & Architectural Faculty of Eskisehir Osmangazi University / Eskişehir Osmangazi Üniversitesi Mühendislik ve Mimarlık Fakültesi Dergisi is the property of Eskisehir Osmangazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Putative alkaline hydrothermal systems on Noachian Mars were potentially habitable environments for microorganisms. However, the types of reactions that could have fueled microbial life in such systems and the amount of energy available from them have not been quantitatively constrained. In this study, we use thermodynamic modeling to calculate which catabolic reactions could have supported ancient life in a saponite-precipitating hydrothermal vent system in the Eridania basin on Mars. To further evaluate what this could mean for microbial life, we evaluated the energy potential of an analog site in Iceland, the Strytan Hydrothermal Field. Results show that, of the 84 relevant redox reactions that were considered, the highest energy-yielding reactions in the Eridania hydrothermal system were dominated by methane formation. By contrast, Gibbs energy calculations carried out for Strytan indicate that the most energetically favorable reactions are CO2 and O2 reduction coupled to H2 oxidation. In particular, our calculations indicate that an ancient hydrothermal system within the Eridania basin could have been a habitable environment for methanogens using NH4+ as an electron acceptor. Differences in Gibbs energies between the two systems were largely determined by oxygen—its presence on Earth and absence on Mars. However, Strytan can serve as a useful analog for Eridania when studying methane-producing reactions that do not involve O2. [ABSTRACT FROM AUTHOR]

Reservoir spaces, such as vesicles, 'secondary' amygdales, dissolution caverns and geodes, are widely developed in the Emeishan basaltic lavas in the Zhoudaping section, Leshan, west Sichuan, China. The dissolution characteristics, cementation sequences, hydrothermal activity stages, as well as fluid types, and their effects on the reservoir capacity were investigated for each stage. Macroscopically, the dissolution features present as irregular dissolution zones, which are characterised by a light red colour. Microscopically, in the dissolved zone, the cementation-filling minerals are associated with complex fill sequences, such as quartz/laumontite/chlorite–chlorite/saponite–epidote/celadonite–cryptocrystalline chlorite–laumontite/calcite/quartz. The U–Pb geochronology shows that the age of chlorite fill in amygdales is 235.3 ± 19.6 Ma; the coarse-crystalline quartz inside dissolution caverns/geodes, 124.47 ± 5.63 to 123.84 ± 5.63 Ma; and the siliceous mineral-filled amygdales, 118.34 ± 3.70 to 114.08 ± 3.76 Ma, which correspond to the early Late Triassic and the mid–late Early Cretaceous, respectively. Combined with geochemical characteristics of post-dissolution fill, the amygdales are affected by two stages of hydrothermal activity: chlorite filling of the amygdales corresponds to post-magma hydrothermal fluids during the early Late Triassic, and the siliceous mineral-fill in amygdales corresponds to deep-sourced hydrothermal fluids during the mid–late Early Cretaceous. The geodes/dissolution caverns result from a single stage of hydrothermal activity related to the mid–late Early Cretaceous deep-source low-temperature hydrothermal fluid. The Late Triassic post-magma hydrothermal fluids are generally destructive to pores, and tectonic-related dissolution of deep-sourced hydrothermal fluids has a positive effect on the formation of reservoir spaces, greatly enhancing fluid storage and flow capacities of the volcanic lavas. We recommend the multi-stage hydrothermal dissolution during Late Triassic–Early Cretaceous and faults, fractures and columnar joints be the focus of hydrocarbon exploration. The reservoir spaces developed in the Zhoudaping section, such as amygdales, dissolution caverns and geodes, were controlled by different stages and types of hydrothermal alteration. Amygdales are the product of two hydrothermal events, which correspond to post-magma hydrothermal fluids during the early Late Triassic and the deep-sourced hydrothermal fluids of the mid–late Early Cretaceous. Geodes/dissolution caverns are affected by deep-source low-temperature hydrothermal fluids in the mid–late Early Cretaceous. The multi-stage hydrothermal dissolution during the Late Triassic–Early Cretaceous and faults, fractures and columnar joints should be the focus of hydrocarbon exploration. [ABSTRACT FROM AUTHOR]

The Eberswalde crater paleolake system on Mars is home to an intact source‐to‐sink fluvial system where a catchment terminates in a river delta deposit. Through analysis of topographic and hyperspectral data from multiple geographic regions, we test the hypothesis that the smectites found within the Eberswalde deposit formed during the Noachian (i.e., >3.5 Ga) in the subsurface and are fluvial detritus transported during the Hesperian (i.e., 3.5–2.0 Ga). We find that the spectra from four pertinent regions (northwest Noachis Terra, Holden crater, and the Eberswalde watershed and delta deposit) are consistent with each other, and most consistent with Fe/Mg smectite clays, namely nontronite and saponite. This points to a detrital origin for the clays observed within Eberswalde crater. Analysis of the watershed also indicates that they likely formed within the subsurface, which previous studies suggest is the location most amenable to the preservation of evidence of past life on Mars. Furthermore, the presence of detrital clays, and not authigenic, indicates that the lake was ∼neutral‐pH and a potentially habitable environment. Taken together, these observations indicate that: (a) within Eberswalde crater is a delta deposit that formed in a habitable environment, (b) that the deposit is composed of minerals that formed during the most habitable period in Mars' history, and (c) those minerals formed in an environment with strong potential to preserve evidence of life. Lastly, the similarities between the Eberswalde fluvial system and the Jezero system make it a compelling site as a standard of comparison by NASA's Perseverance Rover. Plain Language Summary: The geology of Eberswalde crater, Mars, indicates that it was once home to a neutral‐pH, habitable lake early in Mars' history (about 2.0–3.5 billion years ago). The clay minerals that were deposited by the river that filled the lake likely formed in wet‐subsurface conditions earlier in Mars' history (earlier than 3.5 billion years ago). Wet‐subsurface conditions early in Mars' history are thought to be the time and place that were most conducive to life on the Red Planet. Thus, the geologic evidence in and around the Eberswalde crater indicates that it has a strong possibility of preserving evidence of past life on Mars, if life ever existed there. Notably, this deposit, rich in biopreservation potential, is remarkably similar to the deposit in Jezero crater, where NASA's Perseverance Rover is currently exploring, which makes it a strong candidate for comparison to the Jezero crater system. Key Points: Detrital clays within the Eberswalde crater delta deposit point to an ancient neutral‐pH habitable lacustrine environmentDelta deposit sediment was likely sourced from the Noachian subsurface, a high biopreservation potential environmentThe clay‐rich river delta deposit at Eberswalde crater parallels that of Jezero crater, the current home of NASA's Perseverance Rover [ABSTRACT FROM AUTHOR]

Context. The current period is conducive to exploring our Solar System's origins with recent and future space sample return missions, which provide invaluable information from known Solar System asteroids and comets The Hayabusa2 mission of the Japan Aerospace Exploration Agency (JAXA) recently brought back samples from the surface of the Ryugu carbonaceous asteroid. Aims. We aim to identify the different forms of chemical composition of organic matter and minerals that constitute these Solar System primitive objects, to shed light on the Solar System's origins. Methods. In this work, we recorded infrared (IR) hyper-spectral maps of whole-rock Ryugu asteroid samples at the highest achievable spatial resolution with a synchrotron in the mid-IR (MIR). Additional global far-IR (FIR) spectra of each sample were also acquired. Results. The hyper-spectral maps reveal the variability of the functional groups at small scales and the intimate association of phyl-losilicates with the aliphatic components of the organic matter present in Ryugu. The relative proportion of column densities of the identified IR functional groups (aliphatics, hydroxyl + interlayer and/or physisorbed water, carbonyl, carbonates, and silicates) giving access to the composition of the Ryugu samples is estimated from these IR hyper-spectral maps. Phyllosilicate spectra reveal the presence of mixtures of serpentine and saponite. We do not detect anhydrous silicates in the samples analysed, at the scales probed. The carbonates are dominated by dolomite. Aliphatics organics are distributed over the whole samples at the micron scale probed with the synchrotron, and intimately mixed with the phyllosilicates. The aromatic C=C contribution could not be safely deconvolved from OH in most spectra, due to the ubiquitous presence of hydrated minerals. The peak intensity ratios of the organics methylene to methyl (CH2/CH3) of the Ryugu samples vary between about 1.5 and 2.5, and are compared to the ratios in chondrites from types 1 to 3. Overall, the mineralogical and organic characteristics of the Ryugu samples show similarities with those of CI chondrites, although with a noticeably higher CH2/CH3 in Ryugu than generally measured in C1 chondrites collected on Earth, and possibly a higher carbonate content. [ABSTRACT FROM AUTHOR]