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The chelating and sequestering ability of a glyphosate metabolite, the aminomethylphosphonic acid (AMPA) towards bi- and trivalent metal cations, such as Ca 2+ , Mg 2+ , Zn 2+ , Cu 2+ and Al 3+ , were investigated in aqueous solutions of NaCl, in an ionic strength range of 0.1 ≤ I/mol dm -3  ≤ 1.0 and at constant temperature of T = 298.15 ± 0.15 K. The investigations on the acid-base properties and complexing ability were performed, by means of potentiometry, in conditions of different c M :c AMPA molar ratios and pH values. The formation of insoluble species was experimentally observed in the M n+ /AMPA 2- systems, and the solid phases were characterized by means of X-Ray Diffractometry (XRD), Scanning Electron Microscopy (SEM) and InfraRed Attenuated Total Reflection spectroscopy (IR-ATR). The dependence on ionic strength of the stability constants of the M n+ /AMPA 2- complexes species, determined at different ionic strengths, was modelled by the Debye-Hückel type equation. The sequestering ability of AMPA toward the investigated metal cations was evaluated by pL 0.5 parameter., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

In the recent years a considerable effort has been devoted to foster the understanding of the basic mechanisms underlying the dynamical arrest that is involved in glass forming in supercooled liquids and in the sol-gel transition. The elucidation of the nature of such processes represents one of the most challenging unsolved problems in the field of material science. In this context, two important theories have contributed significantly to the interpretation of these phenomena: the Mode-Coupling theory (MCT) and the Percolation theory (PT). These theories are rooted on the two pillars of statistical physics, universality and scale laws, and their original formulations have been subsequently modified to account for the fundamental concepts of Energy Landscape (EL) and of the universality of the fragile to strong dynamical crossover (FSC). In this review, we discuss experimental and theoretical results, including Molecular Dynamics (MD) simulations, reported in the literature for colloidal and polymer systems displaying both glass and sol-gel transitions. Special focus is dedicated to the analysis of the interferences between these transitions and on the possible interplay between MCT and PT. By reviewing recent theoretical developments, we show that such interplay between sol-gel and glass transitions may be interpreted in terms of the extended F13 MCT model that describes these processes based on the presence of a glass-glass transition line terminating in an A3 cusp-like singularity (near which the logarithmic decay of the density correlator is observed). This transition line originates from the presence of two different amorphous structures, one generated by the inter-particle attraction and the other by the pure repulsion characteristic of hard spheres. We show here, combining literature results with some new results, that such a situation can be generated, and therefore experimentally studied, by considering colloidal-like particles interacting via a hard core plus an attractive square well potential. In the final part of this review, scaling laws associated both to MCT and PT are applied to describe, by means of these two theories, the specific viscoelastic properties of some systems.

The prospects, needs and limits in current approaches in catalysis to accelerate the transition to e -chemistry, where this term indicates a fossil fuel-free chemical production, are discussed. It is suggested that e -chemistry is a necessary element of the transformation to meet the targets of net zero emissions by year 2050 and that this conversion from the current petrochemistry is feasible. However, the acceleration of the development of catalytic technologies based on the use of renewable energy sources (indicated as reactive catalysis) is necessary, evidencing that these are part of a system of changes and thus should be assessed from this perspective. However, it is perceived that the current studies in the area are not properly addressing the needs to develop the catalytic technologies required for e -chemistry, presenting a series of relevant aspects and directions in which research should be focused to develop the framework system transformation necessary to implement e -chemistry., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

We report on the facile synthesis of SiO 2 @nitrized-TiO 2 nanocomposite (NST) by calcination of TiO 2 xerogel with OctaAmmonium POSS® (N-POSS; POSS=polyhedral oligomeric silsesquioxanes). The as-obtained nanoporous mixed oxide is constituted by uniformly distributed SiO 2 and nitrized-TiO 2 , where the silica component is present in an amorphous state and TiO 2 in an anatase/rutile mixed phase (92.1 % vs. 7.9 %, respectively) with very small anatase crystallites (3.7 nm). The TiO 2 lattice is nitrized both at interstitial and substitutional positions. NST features a negatively charged surface with a remarkable surface area (406 m 2  g -1 ), endowed with special adsorption capabilities towards cationic dyes. Its photocatalytic behavior was tested by following the degradation of standard aqueous methylene blue and methyl orange solutions under UV and visible light irradiation, according to ISO 10678:2010. For comparison, analogous investigations were carried out on a silica-free N-TiO 2 , obtained by using NH 4 Cl as nitrogen source., (© 2021 The Authors. Published by Wiley-VCH GmbH.)

NMR spectroscopy is used in the temperature range 180-350 K to study the local order and transport properties of pure liquid water (bulk and confined) and its solutions with glycerol and methanol at different molar fractions. We focused our interest on the hydrophobic effects (HE), i.e., the competition between hydrophilic and hydrophobic interactions. Nowadays, compared to hydrophilicity, little is known about hydrophobicity. Therefore, the main purpose of this study is to gain new information about hydrophobicity. As the liquid water properties are dominated by polymorphism (two coexisting liquid phases of high and low density) due to hydrogen bond interactions (HB), creating (especially in the supercooled regime) the tetrahedral networking, we focused our interest to the HE of these structures. We measured the relaxation times (T1 and T2) and the self-diffusion (DS). From these times, we took advantage of the NMR property to follow the behaviors of each molecular component (the hydrophilic and hydrophobic groups) separately. In contrast, DS is studied in terms of the Adam-Gibbs model by obtaining the configurational entropy (Sconf) and the specific heat contributions (CP,conf). We find that, for the HE, all of the studied quantities behave differently. For water-glycerol, the HB interaction is dominant for all conditions; water-methanol, two different T-regions above and below 265 K are observable, dominated by hydrophobicity and hydrophilicity, respectively. Below this temperature, where the LDL phase and the HB network develops and grows, with the times and CP,conf change behaviors leading to maxima and minima. Above it, the HB becomes weak and less stable, the HDL dominates, and hydrophobicity determines the solution.

Molecular mechanisms for N 2 fixation (solar NH 3 ) and CO 2 conversion to C2+ products in enzymatic conversion ( nitrogenase ), electrocatalysis, metal complexes and plasma catalysis are analyzed and compared. It is evidenced that differently from what is present in thermal and plasma catalysis, the electrocatalytic path requires not only the direct coordination and hydrogenation of undissociated N 2 molecules, but it is necessary to realize features present in the nitrogenase mechanism. There is the need for (i) a multi-electron and -proton simultaneous transfer, not as sequential steps, (ii) forming bridging metal hydride species, (iii) generating intermediates stabilized by bridging multiple metal atoms and (iv) the capability of the same sites to be effective both in N 2 fixation and in CO x reduction to C2+ products. Only iron oxide/hydroxide stabilized at defective sites of nanocarbons was found to have these features. This comparison of the molecular mechanisms in solar NH 3 production and CO 2 reduction is proposed to be a source of inspiration to develop the next generation electrocatalysts to address the challenging transition to future sustainable energy and chemistry beyond fossil fuels.

Bisphenol A (BPA)-free epoxy resins, synthesized from low molecular weight cycloaliphatic compounds, may represents promising materials for stone conservation due to their very appealing and tunable physico-chemical properties, such as viscosity, curing rate and penetration ability, being also easy to apply and handle. Furthermore, alkoxysilanes have been widely employed as inorganic strengtheners since they are easily hydrolysed inside lithic substrates affording SiO linkages with the stone matrix. Taking into account the advantages of these two classes of materials, this work has been focused on the development of innovative conservation materials, based on hybrid epoxy-silica BPA-free resins obtained by reaction of 1,4-cycloexanedimethanol diglycidylether (CHDM-DGE) with various siloxane precursors, i.e. glycidoxypropylmethyldiethoxysilane (GPTMS), tetraethyl orthosilicate (TEOS) and isobutyltrimethoxysilane (iBuTMS), using the 1,8-diaminooctane (DAO) as epoxy hardener. Thanks to Raman spectroscopy the synthesis processes have been successfully monitored, allowing the identification of oxirane rings opening as well as the formation of the cross-linked organic-inorganic networks. In accordance with the spectroscopic data, the thermal studies carried out by TGA and DSC techniques have pointed that GPTMS is a suitable siloxane precursor to synthesize the most stable samples against temperature degradation. GPTMS-containing resins have also shown good performances in the dynamic mechanical analysis (DMA) and in contact angle investigations, with values indicating considerable hydrophobic properties. SEM analyses have highlighted a great homogeneity over the entire observed areas, without formations of clusters and/or aggregates bigger than 45 μm, for the cited materials, confirming the efficiency of GPTMS as coupling agent to enhance the organic/inorganic interphase bonding. The variations provided by the incorporation of nanostructured titania, specifically synthesized, inside the epoxy-silica hybrids have been also evaluated. According to all the collected results, the hybrid materials here reported have proven to be promising multifunctional products for potential application in the field of stone conservation., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The future feasibility of decarbonized industrial chemical production based on the substitution of fossil feedstocks (FFs) with renewable energy (RE) sources is discussed. Indeed, the use of FFs as an energy source has the greatest impact on the greenhouse gas emissions of chemical production. This future scenario is indicated as "solar-driven" or "RE-driven" chemistry. Its possible implementation requires to go beyond the concept of solar fuels, in particular to address two key aspects: i) the use of RE-driven processes for the production of base raw materials, such as olefins, methanol, and ammonia, and ii) the development of novel RE-driven routes that simultaneously realize process and energy intensification, particularly in the direction of a significant reduction of the number of the process steps., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A 2-year-old male mongrel dog was presented because of the onset of dry cough. About 16 hours before, the dog had been exposed to the pesticide that the owner was spraying in the vineyard. Approximately 3 hours later an acute respiratory failure, with a rapid evolution, began. Hemoptysis and regenerative normocytic normochromic anemia arose within hours, and a pulmonary hemorrhage was diagnosed. Pulmonary hemorrhage fast led to pneumonia, as evidenced by the serial CXR findings and the developing of leukocytosis. The hypothesis that we believe more likely is that the dog inhaled an amount of copper sulfate powder enough to determine respiratory tree damage, extending from the trachea to the pulmonary alveoli. Oxygen supplementation, antibiotics, antioxidant, and gastroprotective medications had been administered. After 4 days of hospitalization the dog was discharged. After a follow-up of more than 2 years later, the dog is still alive and in good health. To the authors knowledge no evidences of acute pulmonary involvement after copper sulfate inhalation exist in any species. This report is a contribution to the knowledge of copper poisoning, scarcely mentioned both in human and veterinary literature, and which has never been described in companion animals., (Copyright © 2017 Elsevier Inc. All rights reserved.)

The new scenario for sustainable (low-carbon) chemical and energy production drives the development of new biorefinery concepts (indicated as biofactories) with chemical production at the core, but flexible and small-scale production. An important element is also the integration of solar energy and CO2 use within biobased production. This concept paper, after shortly introducing the motivation and recent trends in this area, particularly at the industrial scale, and some of the possible models (olefin and intermediate/high-added-value chemicals production), discusses the opportunities and needs for research to address the challenge of integrating bio- and solar refineries. Aspects discussed regard the use of microalgae and CO2 valorization in biorefineries/biofactories by chemo- or biocatalysis, including possibilities for their synergetic cooperation and symbiosis, as well as integration within the agroenergy value chain., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The use of biomass, bio-waste and CO2 derived raw materials, the latter synthesized using H2 produced using renewable energy sources, opens new scenarios to develop a sustainable and low carbon chemical production, particularly in regions such as Europe lacking in other resources. This tutorial review discusses first this new scenario with the aim to point out, between the different possible options, those more relevant to enable this new future scenario for the chemical production, commenting in particular the different drivers (economic, technological and strategic, environmental and sustainability and socio-political) which guide the selection. The case of the use of non-fossil fuel based raw materials for the sustainable production of light olefins is discussed in more detail, but the production of other olefins and polyolefins, of drop-in intermediates and other platform molecules are also analysed. The final part discusses the role of catalysis in establishing this new scenario, summarizing the development of catalysts with respect to industrial targets, for (i) the production of light olefins by catalytic dehydration of ethanol and by CO2 conversion via FTO process, (ii) the catalytic synthesis of butadiene from ethanol, butanol and butanediols, and (iii) the catalytic synthesis of HMF and its conversion to 2,5-FDCA, adipic acid, caprolactam and 1,6-hexanediol.