Nickel titanium oxide

Post-reaction STEM examinations were also performed on a series of nickel-titanium oxide specimens which had been treated for 1 h in a flow reactor in 10% hydrogen/argon at atmospheric pressure and temperatures from 970 to 1120 K. Prior to removal from the reaction zone, specimens were passivated by cooling to room temperature in flowing argon followed by exposure to a flow of 2% carbon dioxide-argon for 1 h. As will be demonstrated later, careful passivation is necessary to ascertain the corresponding chemical state of the specimen from a post-reaction examination. 

Finally, one may ask why the attack of titania by nickel (e.g., formation of pits) has not been observed in previous studies where nickel/titanium oxide samples had been treated in hydrogen and examined by electron microscopy (6,12,13). In these previous cases, the nickel particles were considerably smaller (5 to 10 nm) than the ones formed in the present experiments ( 100 nm) and therefore the extent of reaction may have been only sufficient to cause removal of a few monolayers of titania, which would be difficult to detect. 

CAS 12035-39-1 EINECS/ELINCS 234-825-4 Synonyms Nickel titanium oxide Titanium nickel oxide Empirical NiOsTi Properties M.w. 154.61... 

Nickel titanium oxide. See Nickel titanate Nickel titanium yellow. See Titanium nickel yellow Nitration benzene. See Benzene Nitric acid, bismuth (3+) salt. See Bismuth nitrate Nitric acid, magnesium salt Nitric acid, magnesium salt (2 1). See Magnesium nitrate... 

CAS 12035-39-1 EINECS/ELINCS 234-825-4 Synonyms Nickel titanium oxide Titanium nickel oxide Empirical NiO Ti Properties M.w. 154.61 Toxicology ACGIH TLV/TWA 0.1 mg(Ni)/m harmful solid irritant sensitizer experimental carcinogen and tumorigen target organ lungs TSCA listed... 

Nickel titanium oxide. See Nickel titanate Nickel titanium yellow. See Titanium nickel yellow... 

Reusing S., Santos-Lopez D., Aegerter M.A. Anodic electrochromic Nickel-Titanium-oxide sol-gel films as counter electrodes for electrochromic devices. Electrochim. Acta 2004, to be published Rinokuma K., Ogasawara K., Kishimoto A., Takano S., Kudo T. Electrochromism of spin-coated Mo03-nH20 thin films from peroxo-polymolybdate. Solid State Ion. 1992 53-56 507-512... 

Other related nickel-containing yellow pigments include antimony nickel titanium oxide and nickel-based azo-metal complexes. 

X-ray diffraction enabled researchers to understand the microstructure of crystalline materials. To reveal the bonding mechanism of hermetic titanium alloys to yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramic-brazed joints, X-ray diffraction analysis on the fractured braze joints was conducted and revealed that the nickel titanium oxide (Ni2Ti40) formed at the zirconia ceramic to titanium metal interface is responsible for the bonding [15]. 

The vapor-phase conversion of aniline to DPA over a soHd catalyst has been extensively studied (18,22). In general, the catalyst used is pure aluminum oxide or titanium oxide, prepared under special conditions (18). Promoters, such as copper chromite, nickel chloride, phosphoric acid, and ammonium fluoride, have also been recommended. Reaction temperatures are usually from 400 to 500°C. Coke formed on the catalyst is removed occasionally by burning. In this way, conversions of about 35% and yields of 95% have been reported. Carba2ole is frequently a by-product. 

Commonly, blends of organic pigments with suitable inorganic pigments are used, such as nickel titanium yellow, chrome titanium yellow, bismuth-molybdenum-vanadium-oxide, or iron oxide. 

Although the titanium oxide layer at the surface of the nitinol is highly biocompatible and protects the underlying substrate from electrochemical corrosion, the titanium oxide layer itself is mechanically very brittle. Under mechanical stress, such as the shear of blood flow in the aorta or under the bending moments of aortic pulsations, the titanium oxide surface layer can fracture, exposing the underlying metal to corrosion. Not only is corrosion undesirable in terms of biocompatibility (i.e., leaching of nickel and its... 

The lag between the time that nitinol, was first produced and the time it was used commercially in medical devices was due in part to the fear that nickel would leach from the metal and not be tolerable as a human implant. As it turns out, with a correct understanding of the surface electrochemistry and subsequent processing, a passivating surface layer can be induced by an anodizing process to form on the nitinol surface. It is comprised of titanium oxide approximately 20 mn thick. This layer actually acts as a barrier to prevent the electrochemical corrosion of the nitinol itself. Without an appreciation for the electrochemistry at its surface, nitinol would not be an FDA-approved biocompatible metal and an entire generation of medical devices would not have evolved. This is really a tribute to the understanding of surface electrochemistry within the context of implanted medical devices. 

Gray. Nickel oxide with titanium oxide... 

Ferrocene is only one of a large number of compounds of transition metals with the cyclopentadienyl anion. Other metals that form sandwich-type structures similar to ferrocene include nickel, titanium, cobalt, ruthenium, zirconium, and osmium. The stability of metallocenes varies greatly with the metal and its oxidation state ferrocene, ruthenocene, and osmocene are particularly stable because in each the metal achieves the electronic configuration of an inert gas. Almost the ultimate in resistance to oxidative attack is reached in (C5H5)2Co , cobalticinium ion, which can be recovered from boiling aqua regia (a mixture of concentrated nitric and hydrochloric acids named for its ability to dissolve platinum and gold). In cobalticinium ion, the metal has the 18 outer-shell electrons characteristic of krypton. 

This problem has been partially overcome by elimination of the phosphorus-oxygen bonds, as, for example, in the poly(phosphinoisocyanates), which have the structure shown in 6.47.42 It is also possible to form poly(metal phosphinates) with repeat unit -M(0PR20)2- by allowing a metal alkoxide to react with a phosphinic acid.43 Typical metal atoms are aluminum, cobalt, chromium, nickel, titanium, and zinc.43 Polymeric phosphine oxides can be prepared by the reactions... 

An increasing number of colored inorganic pigments are FDA-compliant. Historically, yellow iron oxide, red iron oxide, black iron oxide, zinc ferrite, burnt umber, raw and burnt sienna, channel carbon black, chromium oxide green, ultramarine blue, cobalt blue and copper chrome black have enjoyed FDA—compliant status, under 21 CFR 178.3297, Colorants for Polymers . More recently, the FDA has been successfully petitioned with regard to nickel titanium yellow, chrome titanium yellow, and cobalt green under 21 CFR 170.39, Threshold of Regulation for Substances Used in Food-Contact Articles . 

Some metal oxides (notably alumina, magnesia and silica) can be readily prepared in a stable state of high specific surface area. Because of their technical importance as adsorbents, they have been featured in many fundamental and applied investigations of adsorption. Other oxides (e.g. those of chromium, iron, nickel, titanium and zinc) tend to give surfaces of lower area, but exhibit specific adsorbent and catalytic activity. These oxides have also attracted considerable interest. 

Manganese dioxide, sodium nickel hexacynaoferrate, hydrous titanium oxide, zirconium phosphate, ferric hydroxide, different commercial sorbents... 

Many other metal ions have been reported as catalysts for oxidations of paraffins or intermediates. Some of the more frequently mentioned ones include cerium, vanadium, molybdenum, nickel, titanium, and ruthenium [21, 77, 105, 106]. These are employed singly or in various combinations, including combinations with cobalt and/or manganese. Activators such as aldehydes or ketones are frequently used. The oxo forms of vanadium and molybdenum may very well have the heterolytic oxidation capability to catalyze the conversion of alcohols or hydroperoxides to carbonyl compounds (see the discussion of chromium, above). There is reported evidence that Ce can oxidize carbonyl compounds via an enol mechanism [107] (see discussion of manganese, above). Although little is reported about the effectiveness of these other catalysts for oxidation of paraffins to acetic acid, tests conducted by Hoechst Celanese have indicated that cerium salts are usable catalysts in liquid-phase oxidation of butane [108]. 

Manganese dioxide Sodium oxide Nickel II oxide Phosphorus pentoxide Lead oxide Stannous oxide Titanium dioxide Vanadium pentoxide Zirconium oxide... 

Non-stoichiometric oxides may contain either an excess of metal (e.g. zinc oxide, Zni+jO) or a deficiency of metal (e.g. nickel oxide, Ni,.jO). Some metal oxides (e.g. titanium oxide) may be prepared as either excess-metal or metal-deficit oxides. Excess metal is incorporated in the structure as interstitial cations together with the electrons removed through ionization. In metal-deficit or excess-oxygen oxides, excess oxygen is incorporated in the structure by formation of cation vacancies and positive holes, which may be achieved by oxidation of cations, e.g. 

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