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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.

We have investigated the dependence of device characteristics of bulk-heterojunction organic thin-film solar cells on the concentration of glycerol and sorbitol addition in poly(3,4-ethylenedioxy thiophene):poly(4-styrene sulfonate) (PEDOT:PSS) solutions for fabricating buffer layers. The device structure is ITO/buffer/regioregular poly(3-hexylthiophene) (P3HT):[6,6]-phenyl C₆₁-butyric acid methylester (PCBM)/Al. Glycerol addition is effective for increasing power conversion efficiency (PCE) from 1.25 to 1.41% because of the increase in short-circuit current density (J_sc) without decreasing open-circuit voltage (V_oc). On the other hand, sorbitol addition decreases PCE from 1.25 to 1.04%, owing to the decrease in V_oc. This difference in V_oc behavior is ascribed to different work function of PEDOT:PSS with glycerol and sorbitol treatment.

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.

Nowadays tools based on Scanning Probe Methods (SPM) have become indispensable in a wide range of applications such as cell imaging and spectroscopy, profilometry, or surface patterning on a nanometric scale. Common to all SPM techniques is a typically slow working speed which is one of their main drawbacks. The SPM speed barrier can be improved by operating a number of probes in parallel mode. A key element when developing probe array devices is a convenient read-out system for measurements of the probe deflection. Such a read-out should be sufficiently sensitive, resistant to the working environment, and compatible with the operation of large number of probes working in parallel. In terms of fabrication, the geometrical uniformity i.e. the realisation of large numbers of identical probes, is a major concern but also the material choice compatible with high sensitivity, the detection scheme and the working environment is a challenging issue. Examples of promising applications using parallel SPM are dip-pen-nanolithography, data storage, and parallel imaging.