Brookite


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brookite

[′bru̇‚kīt]
(mineralogy)
TiO2 A brown, reddish, or black orthorhombic mineral; it is trimorphous with rutile and anatase, has hardness of 5.5-6 on Mohs scale, and a specific gravity of 3.87-4.08. Also known as pyromelane.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Brookite

 

a mineral of composition TiO2. Sometimes contains admixtures of iron and niobium. Layered structure, consisting of octahedral groups of TiO6, united by common ribs. Crystallizes in a rhombic system. The crystals are usually tabular, less frequently prismatic and dipyramidal. Their color is yellowish brown to reddish brown; their luster is adamantine or metallic. The hardness of brookite on the mineralogical scale is 5.5-6; density, 3,900-4,200 kg/m3. The crystals are found in gold placers and in alpine-type veins in the Urals (USSR); abroad the mineral is found in Switzerland, France, Austria, and the USA.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
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Brookite and anatase are metastable while rutile is most stable phase.
ASSESSMENT OF ANTIOXIDANT AND ANTIBACTERIAL ACTIVITIES OF IRON-TITANIUM OXIDE NANOPARTICLES SYNTHESIZED IN VARIOUS SOLVENTS AND THEIR MICROSCOPIC CHARACTERIZATION
Amorph, brookite, anatase, and rutile forms of Ti[O.sub.2] nanoparticles (Grafen Chemical Industries, Ankara, Turkey) were coated with PEG and BSA.
Induction of Apoptosis and Inhibition of Invasion in Gastric Cancer Cells by Titanium Dioxide Nanoparticles
Brookite phase is also metastable but difficult to synthesize, hence it is seldom studied [20].
A Brief Overview of Ti[O.sub.2] Photocatalyst for Organic Dye Remediation: Case Study of Reaction Mechanisms Involved in Ce-Ti[O.sub.2] Photocatalysts System
Titanium oxide is found in three different crystalline forms: rutile, anatase, and brookite. The anatase phase has been reported to display higher photocatalytic activity than the others, owing to its higher density of localized states [31].
Synthesis and Characterization of CuO, Ti[O.sub.2], and CuO-Ti[O.sub.2] Mixed Oxide by a Modified Oxalate Route
It is well known that Ti[O.sub.2] has three polymorphs phases in nature: rutile, anatase, and brookite; the band gap of rutile phase and anatase phase are 3.0 eV and 3.2 eV, respectively.
Enhancement of Dye-Sensitized Solar Cells Efficiency Using Mixed-Phase Ti[O.sub.2] Nanoparticles as Photoanode
While those of TiO2 powders are mainly from rutile phase (card number: 21-1276), followed by brookite (card number: 79-1973).
Determination of Trace Amounts of Copper in Environmental Water Samples by Flame Atomic Absorption Spectrometry after Preconcentration on TiO2 Nanotubes
It is found in three crystalline phases: brookite (orthorhombic), anatase (tetragonal) and rutile (tetragonal), wherein the anatase and rutile phases are commonly used in photocatalysis, which the anatase phase is considered the highest catalytic activity (Linsebigler, Lu, & Yates, 1995).
Photodegradation of sugarcane vinasse: evaluation of the effect of vinasse pre-treatment and the crystalline phase of Ti[O.sub.2]/ Fotodegradacao da vinhaca: avaliacao do efeito do pre-tratamento da vinhaca e da fase cristalina do Ti[O.sub.2]
(26.) Reyes-Coronado, D, Rodriguez-Gattorno, G, EspinosaPesqueira, ME, Cab, C, de Coss, R, Oskam, G, "Phase-Pure Ti[O.sub.2] Nanoparticles: Anatase, Brookite and Rutile." Nanotechnology, 19 763-770 (2008)
Doped Ti[O.sub.2] nanophotocatalysts for leather surface finishing with self-cleaning properties
The molecular weight is 79.865, melting point 1843[degrees]C, Four naturally occurring titanium dioxide polymorphs exist : rutile, anatase, brookite and titanium dioxide .
Polymeric complexes related a rubber basis
The 'high-1' and 'good' reservoir quality (classes I and III, respectively) quartz sandstones from the E6 structure are mainly composed of quartz, with minor amounts of clay (illite and/or kaolinite) and carbonate cement forming minerals, admixture of feldspar and accessory minerals represented by pyrite, barite, anatase and/or brookite and zircon (Shogenov et al.
Reservoir quality and petrophysical properties of Cambrian sandstones and their changes during the experimental modelling of C[O.sub.2] storage in the Baltic Basin/Kambriumi liivakivide reservuaarikvaliteet ja petrofuusikalised omadused ning nende evolutsioon Balti basseinis C[O.sub.2] geoloogilise ladustamise eksperimentaalse modelleerimise valtel
Ti[O.sub.2] crystallizes in three major structures: rutile (tetragonal), anatase (tetragonal), and brookite (rhombohedrical) (11).
Corrosion studies of thermal sprayed HA and HA/ [Al.sub.2][O.sub.3]-Ti[O.sub.2] bond coating on 316L staneless steel

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