Free-standing cellulose film containing manganese dioxide nanoparticles and its use in discoloration of indigo carmine dye.

In this study, we report the production of a free-standing film of non-modified cellulose impregnated with 12 wt.% of MnO nanoparticles with less than 100 nm in size. The method here described can be applied to the immobilization of different types of nanoparticles.

Production of self-supported conductive films based on cellulose, polyaniline and silver nanoparticles.

Synthetic efforts are being made to produce electrical conductive films based on a combination of cellulose matrix with conducting polymers. Improved mechanical properties and processability of the conducting polymers can be attained by promoting this combination, allowing the production of electrical conductive membranes or sheet of paper-like forms that have many technological uses. Cellulose films containing different amounts of polyaniline combined to silver nanoparticles were prepared in homogenous conditions by the dissolution of microcrystalline cellulose in 1-butyl-3-methylimidazolium chloride ionic liquid, followed by the mixing with dispersion of silver nanoparticles and polyaniline also prepared in an ionic liquid.

The tooth as a monitor of cholestatic liver disease in rats.

Objective: Measure, noninvasively, the deposition of bilirubin in the tooth by using DIAGNOdent and correlate it to liver dysfunction.

Study Design: After confirming the capacity of DIAGNOdent to measure varying bile concentrations in plaster blocks, a cholestatic liver disease model was studied to detect increasing bilirubin impregnation in the teeth of rats. Wistar-EPM rats (n = 50) were divided into three groups: (1) BDL: rats submitted to bile duct ligation (BDL); (2) Naïve: rats without procedure; and (3) Sham: rats submitted to laparotomy without BDL (n = 10/period/group).

Structure of tetraalkylammonium ionic liquids in the interlayer of modified montmorillonite.

We perform molecular dynamics simulations of tetraalkylammonium ionic liquids confined in the interlayer of montmorillonite (MMT). We study the structure and energetics of the systems, which consist of cations with two different alkyl chain lengths and several ionic liquid concentrations. The results we obtained for the structure, namely the presence of a strong layering in all systems and the formation of nonpolar domains with interdigitated alkyl chains in some cases, are largely consistent with previous surface force balance experiments performed on similar systems.

A hybrid material assembled by anthocyanins from açaí fruit intercalated between niobium lamellar oxide.

Organic-inorganic hybrid materials can be prepared dispersing organic species into well-defined inorganic nanoblocks. This paper describes the immobilization of natural dyes from the extract of the Brazilian açaí-fruit into two types of layered hexaniobate precursors derived from H(2)K(2)Nb(6)O(17): (i) colloidal dispersion of niobate exfoliated nanoparticles and (ii) niobate pre-intercalated with tetraethylammonium cations (TEA(+)). The restacking of exfoliated particles in the presence of açaí anthocyanins promotes their intercalation and produces stacked layers showing large basal spacing (ca.

Evaluation of hexaniobate nanoscrolls as support for immobilization of a copper complex catalyst.

In this work, we report the intercalation properties of the hexaniobate nanoscrolls toward insertion of 2-[2-(2-pyridyl)ethylimino-1-ethyl]pyridine-imidazole copper(II), [Cu(apip)imH]2+, a cationic complex able to promote the catalytic oxidation of organic substrates. Hexaniobate was first transformed into its acidic phase, H2K2Nb6O17, and then exfoliated with n-butylamine in water. The copper complex was immobilized into the nanoscrolls obtained by the acidification of delaminated particle dispersion at pH 3.