Advances in gamma titanium aluminides and their manufacturing techniques

Heated goethite and natural hematite: Can Raman spectroscopy be used to differentiate them?

Magnetite nanoparticles for biomedical applications are typically prepared using the coprecipitation technique, which is the most convenient method. However, the reaction pathways leading to the production of the magnetite phase in the coprecipitation reaction are not fully understood, despite the fact that the reaction path may be of significant importance in controlling the crystal structure, morphology, and particle size of the magnetite nanoparticles. In the present study, we identified the reaction pathways in the coprecipitation of magnetite; when base was slowly added to an iron chloride solution, akaganeite nucleated and transformed through goethite to magnetite. At high addition rates, an additional pathway in which ferrous hydroxide nucleated and transformed through lepidocrocite to magnetite competed with the former pathway. This difference was due to the pH inhomogeneity in the reaction medium that was present before homogeneous mixing. In most coprecipitation reactions, these magnetite format...

Formation Pathways of Magnetite Nanoparticles by Coprecipitation Method

https://pubs.rsc.org/en/content/articlepdf/2021/GC/D0GC03465G

Recent developments in organocatalysed transformations of epoxides and carbon dioxide into cyclic carbonates

A low-temperature, efficient and one-step deposition method, in which Mn(CH3COO)2?4H2O serves as precursor and O2 as oxidant, was employed to deposit Mn3O4 nanoparticles on multi-walled carbon nanotubes (MWCNTs) in ethanol solution at 150 and 200??C. The resulting Mn3O4/MWCNT composites were characterized by means of different techniques including x-ray diffraction, x-ray photoelectron spectroscopy and transmission electron microscopy. It was indicated that the Mn3O4 nanoparticles were attached uniformly on MWCNTs with sizes less than 10?nm, and the loading amount of Mn3O4 could be tuned by changing the initial weight ratio of Mn(CH3COO)2?4H2O/MWCNT. The electrochemical behavior of the Mn3O4/MWCNT composites was examined by cyclic voltammetry, and the result indicated the specific capacitance of the composite electrode was 330?F?g?1, nearly 18 times higher than that of the pure MWCNT electrode. The good performance of the as-prepared composites as electrode material may be attributed to the synergistic effects of the Mn3O4 nanoparticles and the MWCNTs.

https://iopscience.iop.org/article/10.1088/0957-4484/19/27/275709/pdf

Low-temperature synthesis of Mn(3)O(4) nanoparticles loaded on multi-walled carbon nanotubes and their application in electrochemical capacitors.

Study of the mechano-chemical transformation of goethite to hematite by TEM and XRD

Comparative study of two silica mesoporous materials (SBA-16 and SBA-15) modified with a hydroxyapatite layer for clindamycin controlled delivery

Processings of iron oxides at room temperature. I. Solid state conversion of pure α-FeOOH into distinctive α-Fe2O3

Solid state amorphisation in binary systems prepared by mechanical alloying

Meso- and nanoporous structures are adequate matrices for controlled drug delivery systems, due to their large surface areas and to their bioactive and biocompatibility properties. Mesoporous materials of type SBA-15, synthesized under different pH conditions, and zeolite beta were studied in order to compare the different intrinsic morphological characteristics as pore size, pore connectivity, and pore geometry on the drug loading and release process. These materials were characterized by X-ray diffraction, nitrogen adsorption, scanning and transmission electron microscopy, and calorimetric measurements. Ibuprofen (IBU) was chosen as a model drug for the formulation of controlled-release dosage forms; it was impregnated into these two types of materials by a soaking procedure during different periods. Drug loading and release studies were followed by UV-Vis spectrophotometry. All nano- and mesostructured materials showed a similar loading behavior. It was found that the pore size and Al content strongly influenced the release process. These results suggest that the framework structure and architecture affect the drug adsorption and release properties of these materials. Both materials offer a good potential for a controlled delivery system of ibuprofen.

/pdf/infuence-of-microstructure-in-drug-release-behavior-of-53ws910ytx.pdf

A. Sagarzazu

Papers

Study of the mechano-chemical transformation of goethite to hematite by TEM and XRD

Comparative study of two silica mesoporous materials (SBA-16 and SBA-15) modified with a hydroxyapatite layer for clindamycin controlled delivery

Processings of iron oxides at room temperature. I. Solid state conversion of pure α-FeOOH into distinctive α-Fe2O3

Solid state amorphisation in binary systems prepared by mechanical alloying

Infuence of microstructure in drug release behavior of silica nanocapsules.