Potential Prebiotic Relevance of Glycine Single Crystals Enclosing Fluid Inclusions: An Experimental and Computer Simulation with Static Magnetic Fields

Glycine crystallizes into three different polymorphs called α, β and γ under standard physicochemical conditions. They have different features depending on their structural variations. The possible interaction of glycine with magnetic minerals in meteorites and comets or in the ancient Earth, paves the way to study the self-assembly and molecular behavior under irradiation and magnetic conditions. The magnetic field might induce the formation of a specific polymorph of glycine. To gain insight on the consequences of gamma irradiation with a gradient of static magnetic fields (0.06 T, 0.3 T, 0.42 T and 0.6 T) on the self-assembly of single macroscopic glycine crystals, we gamma irradiated the powdered amino acid and then assembled single crystals from water solutions. The preliminary results showed a stable formation of fluid inclusions in the single crystals and no straightforward effect on the self-assem- bly process after glycine gamma irradiation and interaction with static magnetic fields. The α glycine polymorph single crystals formed at 55° from the magnetic longitudinal axis and seemed to be enhanced by gamma radiation. The γ-glycine single crystals presented L and D circular dichroism signals, whereas the irradiated samples presented no circular dichroism bands. Com- puter simulations suggest different catalytic properties from α and γ glycine crystals.

Study of an Ionic Fluid on the Electrochemical Test of A36 Carbon Steel Ingot

An ionic fluid based on aromatic heterocyclic family constituted by 1,3-diazole groups was investigated. The purpose is to describe their electrochemical characteristics in order to identify the strategy to avoid the A36 carbon steel surface degradation by using electrochemical measurements. We found that the linear polarization resistance reveals an increasing value when the organic unsaturated cyclic ionic fluid was added to the corrosive electrolyte. The polarization curves and Tafel Extrapolation obtained to know the slopes tafel and the inhibitor efficiency from current density (icorr) shows a high efficiency inhibition value.

Synthesis and Structural Characterization of Monocrystalline α-V2O5 Nanowires

A stable one-dimensional system in an orthorhombic α-V2O5 nanowires monocrystalline structure was obtained by a solvothermal method from a polymorphic V2O5 structure. The starting material was firstly submitted to acid hydrolysis in H2O2 followed by a solvothermal treatment. The outcome of this procedure, a metastable phase of the one-dimensional system V10O24·12H2O/V3O7·H2O, was subsequently reoxidized by controlled heating in an open air system. The final product was an orange crystalline solid mainly formed by monocrystalline nanowires of α-V2O5 having lengths of tens of micrometers and widths of about 75 nm with a preferential [200] growth direction. It was found that the pH value of the initial solution plays an important role in the formation of the crystalline phase in the final products. Characterization was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). This study offers an alternate route for the synthesis of vanadium oxides and related compounds.