DFT study of the reaction between VO2+ and C2H6

The molecular mechanisms of the reaction VO2+ ((1)A(1)/(3)A'') + C2H6 ((1)A(g)) to yield V(OH)(2)(+) ((1)Sigma(+)/(3)Sigma(-)) + C2H4 ((1)A(g)) and/or VO+ ((1)Delta/(3)Sigma) + H2O ((1)A(1)) + C2H4 (Ag-1) have been investigated with density functional theory (DFT) at the B3LYP/6-311G(2d,p) level. Calculations including geometry optimization, vibrational analysis, and Gibbs free energy for the stationary points on the reactive potential energy surfaces at both the singlet (s) and first excited triplet (t) electronic states have been carried out. The most thermodynamically and kinetically favorable pathway is the formation of t-V(OH)(2)(+) + C2H4 along a four-step molecular mechanism (insertion, two consecutive hydrogen transfers, and elimination). A crossing point between s and t electronic states has been characterized. A comparison with previous works on VO2+ + C2H4 (Gracia et al. J. Phys. Chem. A 2003, 107, 3107-3120) and VO2+ + C3H8 (Engeser et al. Organometallics 2003, 22, 3933-3943) reactions allows us a rationalization of the different reactivity patterns. The catalytic role of water molecules in the tautomerization process between hydrated oxide cation, VO(H2O)(+,) and dihydroxide cation, V(OH)(2)(+), is achieved by a water-assisted mechanism.

Evaluation of tissue reaction, cell viability and cytokine production induced by Sealapex Plus

The aim of this study was to investigate the effects of mineral trioxide aggregate (MTA), Sealapex, and a combination of Sealapex and MTA (Sealapex Plus) on the reaction of subcutaneous connective tissue of rats, and on cell viability and cytokine production in mouse fibroblasts. The tissue reaction was carried out with dentin tubes containing the materials implanted in the dorsal connective tissue of rats. The histological analysis was performed after 7 and 30 days. Millipore culture plate inserts with polyethylene tubes filled with materials were placed into 24-well cell culture plates with mouse fibroblasts to evaluate the cell viability by MTT assay. ELISA assays were also performed after 24 h of exposure of the mouse fibroblasts to set material disks. Histopathologic examination showed Von Kossa-positive granules that were birefringent to polarized light for all the studied materials at the tube openings. No material inhibited the cell viability in the in vitro test. It was detected IL-6 production in all root-end filling materials. MTA and Sealapex Plus induced a slight raise of mean levels of IL-1β. The results suggest that Sealapex Plus is biocompatible and stimulates the mineralization of the tissue.

Voltammetric Study of a Cubic Silsesquioxane Organically Modified with Imidazole and their Subsequent Reaction with Cadmium and Hexacyanoferrate (III)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Silsesquioxane organofunctionalized with 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole: preparation and subsequent reaction with silver and potassium hexacyanoferrate(III) for detection of l-cysteine

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Drug reaction with Eosinophilia and Systemic Symptoms (DRESS) / Drug-induced Hypersensitivity Syndrome (DIHS): a review of current concepts

The Drug Reaction with Eosinophilia and Systemic Symptoms syndrome, also known as Drug Induced Hypersensitivity Syndrome presents clinically as an extensive mucocutaneous rash, accompanied by fever, lymphadenopathy, hepatitis, hematologic abnormalities with eosinophilia and atypical lymphocytes, and may involve other organs with eosinophilic infiltration, causing damage to several systems, especially to the kidneys, heart, lungs, and pancreas. Recognition of this syndrome is of paramount importance, since the mortality rate is about 10% to 20%, and a specific therapy may be necessary. The pathogenesis is related to specific drugs, especially the aromatic anticonvulsants, altered immune response, sequential reactivation of herpes virus and association with HLA alleles. Early recognition of the syndrome and withdrawal of the offending drug are the most important and essential steps in the treatment of affected patients. Corticosteroids are the basis of the treatment of the syndrome, which may be associated with intravenous immunoglobulin and, in selected cases, Ganciclovir. The article reviews the current concepts involving this important manifestation of adverse drug reaction.

On a comparison method to reaction-diffusion systems and its applications to chemotaxis

In this paper we consider a general system of reaction-diffusion equations and introduce a comparison method to obtain qualitative properties of its solutions. The comparison method is applied to study the stability of homogeneous steady states and the asymptotic behavior of the solutions of different systems with a chemotactic term. The theoretical results obtained are slightly modified to be applied to the problems where the systems are coupled in the differentiated terms and / or contain nonlocal terms. We obtain results concerning the global stability of the steady states by comparison with solutions of Ordinary Differential Equations.

Aqueous Enantioselective Aldol Reaction of Methyl- and Phenylglyoxal Organocatalyzed by N-Tosyl-(S a)-binam-l-prolinamide

The direct aldol reaction between methylglyoxal (40% aqueous solution) or phenylglyoxal monohydrate and ketones or aldehydes is catalyzed by N-tosyl-(S a)-binam-l-prolinamide to afford the corresponding chiral γ-oxo-β-hydroxy carbonyl compounds, mainly as anti isomers with enantioselectivities up to 97%.

Studies relating to the reaction between zirconium and water at high temperatures /

"TID-4500, 12th ed."

Degradation of azo-dye Orange II by a photoassisted Fenton reaction using a novel composite of iron oxide and silicate nanoparticles as a catalyst

A novel nanocomposite of iron oxide and silicate, prepared through a reaction between a solution of iron salt and a dispersion of Laponite clay, was used as a catalyst for the photoassisted Fenton degradation of azo-dye Orange II. This catalyst is much cheaper than the Nafion-based catalysts, and our results illustrate that it can significantly accelerate the degradation of Orange II under the irradiation of UV light (lambda = 254 nm). An advantage of the catalyst is its long-term stability that was confirmed through using the catalyst for multiple runs in the degradation of Orange II. The effects of the H2O2 molar concentration, solution pH, wavelength and power of the LTV light, catalyst loading, and initial Orange II concentration on the degradation of Orange 11 were studied in detail. In addition, it was also found that discoloration of Orange 11 undergoes a faster kinetics than mineralization of Orange II and 75% total organic carbons of 0.1 mM Orange II can be eliminated after 90 min in the presence of 1.0 g of Fe-nanocomposite/L, 4.8 mM H2O2, and 1 x 8W UVC.

Stochastic Modeling of Reversible Biochemical Reaction-Diffusion Systems and High-Resolution Shock-Capturing Methods for Fluid Interfaces

Thesis (Ph.D.)--University of Washington, 2016-08