Results 171 to 180 of about 3,174 (219)

On Brookite Crystals in the Dogger

Geological Magazine, 1938
In the course of work in collaboration with Dr. J. E. Hemingway on the petrography of the Dogger of North-East Yorkshire it has been found that brookite is widely distributed as a “heavy mineral” constituent in several different kinds of sediment. This is in agreement with results obtained earlier by myself alone in the study of sandstones from higher ...
openaire   +1 more source

Sol–gel synthesis of mesoporous anatase–brookite and anatase–brookite–rutile TiO2 nanoparticles and their photocatalytic properties

Journal of Colloid and Interface Science, 2015
TiO2 photocatalysts with a mixture of different TiO2 crystal polymorphs have customarily been synthesized hydrothermally at high temperatures using complicated and expensive equipment. In this study TiO2 nanoparticles with a mixture of TiO2 crystals were synthesized using a modified sol-gel method at low temperature. In order to form nanoparticles with
Bridget K, Mutuma, Godlisten N, Shao, Won Duck, Kim, Hee Taik, Kim   +3 more
openaire   +2 more sources

Photoactivity of brookite–rutile TiO2 nanocrystalline mixtures obtained by heat treatment of hydrothermally prepared brookite

Materials Chemistry and Physics, 2011
Abstract Pure brookite phase was prepared by hydrothermal synthesis of titanium peroxo-complex in the presence of glycolic acid at 220 °C. The structure of prepared brookite samples was determined by X-ray powder diffraction (XRD) and selected area electron diffraction (SAED).
Václav Štengl, Daniela Králová
openaire   +1 more source

The optical absorption edge of brookite TiO2

Solid State Communications, 2006
Abstract The optical absorption edge of brookite TiO2 was measured at room temperature, using natural crystals. The measurements extend up to 3.54 eV in photon energy and 2000 cm−1 in absorption coefficient. The observed absorption edge is broad and extends throughout the visible, quite different from the steep edges of rutile and anatase.
R. Zallen, M.P. Moret
openaire   +1 more source

Facile synthesis of brookite TiO₂ nanoparticles

Chemical Communications, 2020
A simple method has been developed for synthesis of phase-pure and highly crystalline brookite TiO2 nanoparticles from a broad range of titanium precursors.
Aref Mamakhel, Jinlong Yu, Frederik Søndergaard-Pedersen, Peter Hald, Bo Brummerstedt Iversen   +4 more
openaire   +3 more sources

Brookite in the Millstone Grit of Yorkshire

Geological Magazine, 1939
The record by Dr. Rastall (1) of new types of brookite from the Dogger of North-East Yorkshire prompts a note on the brookite of the Millstone Grit of West and South-West Yorkshire, since the brookite of this latter formation presents interesting features somewhat different from those presented by the brookite of the Dogger.
openaire   +1 more source

Controlled synthesis of brookite and combined brookite with rutile phases of titanium di-oxide and its characterization studies

Ceramics International, 2017
Abstract Experimental conditions for the sol-gel synthesis of TiO 2 were modified by using Polyethylene glycol (PEG) as well as an addition of acid catalyst. Synthesis of brookite and mixed brookite with rutile was obtained. X-ray powder diffraction and Micro Raman measurements confirmed the crystallization of brookite while using pure PEG 4000 ...
T. Balaganapathi, B. Kaniamuthan, S. Vinoth, T. Arun, P. Thilakan   +4 more
openaire   +1 more source

EPR of substitutional Fe3+ in TiO2 (Brookite)

Journal of Physics and Chemistry of Solids, 1973
Resume The EPR spectrum of substitutional Fe 3+ in natural crystals of brookite (TiO 2 ) has been analyzed. This represents the first EPR centre to be identified in brookite. The Ka-band data are described by the Hamiltonian parameters: g = 2.002 ± 0.005, D = 0.117 ± 0.006 cm −1 and E = 0.033 ± 0.002 cm −1 .
J.A. Rostworowski, M. Horn, C.F. Schwerdtfeger   +2 more
openaire   +1 more source

Brookite Crystals from Franklin, N.J.

Rocks & Minerals, 1951
(1976). Brookite Crystals from Franklin, N.J. Rocks & Minerals: Vol. 51, A Fifty Year Retrospective, pp. 519-520.
openaire   +1 more source

Hydrothermal Preparation of Nanosized Brookite Powders

Journal of the American Ceramic Society, 2000
Titania powders in pure brookite form were synthesized by hydrothermal treatment of titanium(IV) salt solutions. Two kinds of starting materials, titanium sulfate and titanium tetrachloride, were used in the hydrothermal reactions. The effects of preparation conditions on the polymorphous form and morphology of the titanium dioxide powders were studied.
Yanqing Zheng, Erwei Shi, Suxian Cui, Wenjun Li, Xingfang Hu   +4 more
openaire   +1 more source