Inverse Hall–Petch relation of nanostructured Ni films prepared by electrodeposition

We report the morphology, texture, mechanical properties of Ni films with nanosized grains prepared by electrodeposition as a function of current density. With an increase in current density, the morphology of the nanostructured films was greatly affected and the textures changed from face-centered cubic (1 1 1)- to (2 0 0)-orientation. Consequently, the textural and microstructural alteration exerted strong influence on the hardness of the films, leading to decrease in the hardness (in particular, the inverse Hall–Petch relation) as current density increased, attributed to the distribution of colonies of grain agglomerate and the variation of directional tensile strength.     

Equilibrium adsorption model of anions onto a novel synthesized chelating fiber under various pHs and Fourier transform infrared study of these adsorptions

In this article, we present a new adsorption model of anion particles onto a chelating fiber. Nonideal H⁺ adsorption on the chelating fiber can be described adequately by the use of the heterogeneity factor β and the parameter Φ indicates the geometric factor of effective concentration in this model. The best fits of amines adsorption data were obtained by means of the developed model using two factors. Poly(acrylo‐amidino diethylene diamine) was synthesized as a chelating polymer through the coupling of diethylene triamine with polyacrylonitrile fiber in the presence of AlCl₃ · 6H₂O addition. Chromate ion and phosphate ion adsorption data on the synthesized poly(acrylo‐amidino diethylene diamine) were obtained. Fourier transform infrared studies of these adsorptions were also performed. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 2430–2440, 2004     

Highly porous poly(lactide‐co‐glycolide) microparticles for sustained tiotropium release

In this study, porous poly(lactide‐co‐glycolide) (PLGA) microparticles with low mass density and large particle size were developed for chronic obstructive pulmonary disease treatment using anticholinergic drug (tiotropium). The porous PLGA microparticles were prepared by the water‐in‐oil‐in‐water (W₁/O/W₂) multi‐emulsion method using PLGA polymer and ammonium bicarbonate (as a porogen). Herein, soluble starch was incorporated in porous PLGA microparticles for long‐term tiotropium release. In vitro drug release studies determined that the rapid release of tiotropium from porous PLGA microparticles was reduced because of the high viscosity of the incorporated starch. Tiotropium release from porous PLGA microparticles continued up to 3 days. Furthermore, the inhaled microparticles showed longer drug residence in in vivo lung epithelium. Copyright © 2013 John Wiley & Sons, Ltd.     

Magnetic nanoparticles with hybrid shape

Co₅₀Ni₅₀ particles with very unusual shapes, resembling dumbbells or diabolos, are obtained by reducing mixtures of cobalt and nickel acetates in sodium hydroxide solution in 1,2-propane diol. These particles consist of a central column richer in cobalt than the overall composition, capped with two terminal platelets that are richer in nickel. These hybrid shapes are the result of a two-step growth mechanism due to a difference in reactivity of the two metal ions. The sodium hydroxide concentration controls the length and diameter of the column, in the ranges 50–250 nm and 5–15 nm, respectively, and the diameter of the platelets in the range 25–50 nm. The X-ray diffraction patterns show a mixture of hcp and fcc phases in various proportions depending on the particle shape. High-resolution electron microscopy shows that the hcp phase is located mainly in the central column and the fcc phase mainly in the terminal platelets. The particles are ferromagnetic at room temperature. When the volume fraction of the central column is high enough and the hcp phase is predominant and not much faulted, high coercivity (up to 1900 Oe) is observed.