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Currently, electrochemical anodizing is one of the most common processes in materials science, since, under the right conditions, it allows to modify the material surface without damaging it by means of redox reactions, generating an oxide layer that protects the material and improves its properties. In this paper, grade 2 titanium was anodized using a solution of hydrochloric acid, glycerol, and deionized water as electrolyte, and 0.5 M K₂CrO₄ as doping agent, with a voltage of 30 V for 4.5 h. After anodizing with and without chromium, annealing was performed at different temperatures (500${}^{\circ }$C, 600${}^{\circ }$C and 700${}^{\circ }$C) to promote structural and microhardness changes. The samples were analyzed by FE-SEM observing that the formation of nanostructures changes according to the heat treatment, where samples at 700${}^{\circ }$C with chromium begin to form nanorods and, compared to those without chromium, the nanorods are longer. The presence of Cr in anodized TiO₂ at different temperatures was confirmed by EDS technique. Using XRD, the microstructure of TiO₂ anodized with and without Cr was analyzed and anatase and rutile phases were found, with greater presence of anatase for samples with Cr. Finally, a maximum hardness of up to 10.27 GPa was obtained from the sample at 700${}^{\circ }$C without chromium, which is higher compared to the values of coatings with Cr. However, the anatase phase could be stabilized at higher temperatures making it suitable for medical applications since the anatase phase is the most biocompatible.

This study is a pilot investigation on the effect of using nanosilica for reinforcing thermoplastic starch-based bioplastic films. An arbitrary 0.2wt.% of nanosilica particles were used to reinforce starch derived bioplastic materials and were further investigated for potential benefits. Nanosilica was extracted from rice husk and was characterized using methods like Fourier transform infrared spectroscopy (FTIR) technique and Brunauer–Emmett–Teller (BET) method. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques were used to determine the structure of nanosilica crystals. Scanning electron microscopy (SEM) technique was used to study the surface topography and composition of nano ‘silica. Both raw and reinforced bioplastic films were tested for thermal stability using thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC) tests and their performance was compared. Mechanical properties were compared using tensile and tear tests and biodegradability was assessed through enzymatic degradation analysis. It was found that the presence of nanosilica improved the bonding of polymer matrix and in turn increased the thermal stability and tear strength. Nanosilica reinforced matrix resulted in the increase of surface area than raw bioplastic matrix, which lead to high rate of enzymatic reactivity and degradation rate.

A series of activated carbon (AC) supported Au nanocatalysts with different loadings of Au were prepared by using the homogeneous deposition–precipitation (HDP) method. The samples were characterised with myriad techniques such as X-ray diffraction (XRD), CO-chemisorption, N₂ adsorption–desorption measurements, transmission electron microscopy (TEM), inductively coupled plasma-optical emission spectrometer (ICP-OES) and X-ray photoelectron spectroscopy (XPS) to understand the structural and textural properties in detail. The catalysts were tested for the vapour phase oxidation of glycerol to glyceric acid under base-free medium in an aerobic condition at normal atmospheric pressure. The Au/AC nanocatalysts with smaller size Au particles ($<6$nm) showed higher glycerol conversion and selectivity for glyceric acid, and also a longer catalyst life. While the larger Au particles ($>10$nm) showed less activity and selectivity. Among all the nanocatalysts tested, the 1.0wt.% Au/AC sample having smaller particle size of Au showed the best catalytic performance in terms of glycerol conversion and glyceric acid selectivity. These results suggest that the oxidation activities of Au/AC nanocatalysts are strongly influenced by the size of Au nanoparticle, nature of the support material and through a metal-support interaction.

The first dehydration of protonated glycerol taking place at its secondary site was investigated by density functional calculations by considering different conformations of glycerol. Five parallel reaction pathways via different conformers of protonated glycerol were found. One of these pathways leads to a direct formation of protonated 3-hydroxylpropanal (HPA), another one of these pathways produces protonated glycidol, and the other three produce protonated 3-hydroxy-1,1-propanediol (HPD). One of these pathways producing protonated HPD was found to have obviously larger relative reaction rate than other pathways. The dehydration of protonated HPD to afford protonate HPA requires a rather low reaction barrier (12 kcal/mol). These results show that the production of HPA via a stepwise process with protonated HPD as a key intermediate, is energetically favorable than via a one-step concerted process producing HPA.

The conversion of glycerol to acrolein is an undesirable event in whisky production, caused by infection of the broth with Klebsiella pneumoniae. This organism uses glycerol dehydratase to transform glycerol into 3-hydroxypropanal, which affords acrolein on distillation. The enzyme requires adenosylcobalamin (coenzyme B₁₂) as cofactor and a monovalent cation (e.g. K⁺). Diol dehydratase is a similar enzyme that converts 1,2-diols (C₂-C₄) including glycerol into an aldehyde and water. The subtle stereochemical features of these enzymes are exemplified by propane-1,2-diol: both enantiomers are substrates but different hydrogen and oxygen atoms are abstracted. The mechanism of action of the dehydratases has been elucidated by protein crystallography and ab initio molecular orbital calculations, aided by stereochemical and model studies. The 5'-deoxyadenosyl (adenosyl) radical from homolysis of the coenzyme's Co-C σ-bond abstracts a specific hydrogen atom from C-1 of diol substrate giving a substrate radical that rearranges to a product radical by 1,2-shift of hydroxyl from C-2 to C-1. The rearrangement mechanism involves an acid-base 'push-pull' in which migration of OH is facilitated by partial protonation by Hisα143, synergistically assisted by partial deprotonation of the non-migrating (C-1) OH by the carboxylate of Gluα170. The active site K⁺ ion holds the two hydroxyl groups in the correct conformation, whilst not significantly contributing to catalysis. Recently, diol dehydratases not dependent on coenzyme B₁₂ have been discovered. These enzymes utilize the same kind of diol radical chemistry as the coenzyme B₁₂-dependent enzymes and they also use the adenosyl radical as initiator, but this is generated from S-adenosylmethionine.

The design of a dendrimeric-like diglycerol-tetrasubstituted Zn(II) phthalocyanine resulted in a remarkably water-soluble compound due to the presence of 16 hydroxyls. Several parameters relevant to evaluate the photodynamic efficiency of a potentiel photosensitizer such as: aggregation behavior, fluorescence properties, singlet oxygen generation, binding to a carrier protein model (Bovine Serum Albumin) and partition coefficient have been measured. Biocompatibility was demonstrated by dark cytotoxicity in in vitro experiments. The absence of phototoxicity can be explained by an elevated hydrophilicity. All the collected data have confirmed that this new substitution pattern is promising to be used on phthalocyanines aiming at being photodynamic therapy agents.

The development of electrocatalysts with high activity is essential to convbar glycerol into value-added chemicals through electrocatalytic oxidation. Nano-sized metals with prickly structures are expected to possess high electrocatalytic activity due to the strong electric field at the sharp tips. We propose a facile approach to prepare Au nanoparticles with prickly structure by galvanic displacement in this work. The reaction between Au³⁺ and Ni generates in situ highly dispersed Au nanoparticles with prickly structures on the Ni foam. Owing to appropriate prickly structure, the Au nanoparticles prepared at 25^∘C for 30 s exhibited the best electrocatalytic performance. Finite element simulation method simulations show that the high-density of positive charge at the tips forms strong electric field, which enriches OH⁻ ions and promotes glycerol oxidation, thus exhibiting excellent electrocatalytic activity. This study will guide further design/development of electrocatalytic nanostructured Au particles and provide an effective route to electrocatalytically oxidize glycerol.