Titanyl

Anhydrous titanium dioxide is only soluble with difficulty in hot concentrated sulphuric acid dilution allows the crystallisation of a sulphate of formula T10S04.H20, but it is doubtful if the titanyl cation TiO actually exists, either in solution or the solid. Certainly [TifHjOIn] does not exist, and solutions of titanyl salts may best be considered to contain ions [Ti(0H)2(H204)] . Titanium... 

Only certain types of crystalline materials can exhibit second harmonic generation (61). Because of symmetry considerations, the coefficient must be identically equal to zero in any material having a center of symmetry. Thus the only candidates for second harmonic generation are materials that lack a center of symmetry. Some common materials which are used in nonlinear optics include barium sodium niobate [12323-03-4] Ba2NaNb O lithium niobate [12031 -63-9] LiNbO potassium titanyl phosphate [12690-20-9], KTiOPO beta-barium borate [13701 -59-2], p-BaB204 and lithium triborate... 

Numerous modifications of chromium-based catalysts have been made through the introduction of various additives, the most effective of which are titanium alkoxides (38,39). These additives apparentiy reduce surface silyl chromate moieties to chromium titanates, which are then oxidized to titanyl chromates. These catalysts offer a better control of the resin molecular weight (39). 

The undissolved soHds are removed and the Hquid is evaporated under vacuum and cooled. The precipitated FeSO 7H20 is filtered and the filtrate concentrated to ca 230 g/L. Heating to 90°C hydroly2es titanyl sulfate to insoluble titanyl hydroxide. 

A more recent patent describes the production of titanyl nitrate by electrolysis of titanium tetrachloride or titanyl chloride (37). Other titanium nitrogen compounds that have been described include titanous amide [15190-25-9] Ti(NH2)3, titanic amide [15792-80-0] Ti(NH)2, and various products in which amines have reacted with titanium tetrachloride (38). 

OC-Hydroxycarboxylic Acid Complexes. Water-soluble titanium lactate complexes can be prepared by reactions of an aqueous solution of a titanium salt, such as TiCl, titanyl sulfate, or titanyl nitrate, with calcium, strontium, or barium lactate. The insoluble metal sulfate is filtered off and the filtrate neutralized using an alkaline metal hydroxide or carbonate, ammonium hydroxide, amine, or alkanolamine (78,79). Similar solutions of titanium lactate, malate, tartrate, and citrate can be produced by hydrolyzation of titanium salts, such as TiCl, in strongly (>pH 10) alkaline water isolation of the... 

Similar complexes are formed between poly(viayl alcohol) and titanium lactate (96,101), titanyl sulfate (102), or vanadyl compounds (103). 

Titanyl sulfate (Ti0S04.2H20) [13825-74-6] M 160.0. Dissolved in water, filtered and crystd three times from boiling 45% H2SO4, washing with EtOH to remove excess acid, then with Et20. Air dried for several hours, then oven dried at 105-110°. [Hixson and Fredrickson Ind Eng Chem 37 678 7945.]... 

Discussion. With an acidic titanium(IV) solution hydrogen peroxide produces a yellow colour with small amounts oftitanium(up to 0.5 mg ofTiOz permL), the intensity of the colour is proportional to the amount of the element present. Comparison is usually made with standard titanium(IV) sulphate solutions a method for their preparation from potassium titanyl oxalate is described below. The hydrogen peroxide solution should be about 3 percent strength (ten volume) and the final solution should contain sulphuric acid having a concentration from about 0.75 to 1.75M in order to prevent hydrolysis to a basic sulphate and to prevent condensation to metatitanic acid. The colour intensity increases slightly with rise of temperature hence the solutions to be compared should have the same temperature, preferably 20-25 °C. 

Preparation of standard titanium solution. Weigh out 3.68 g potassium titanyl oxalate K2Ti0(C204)2,2H20 into a Kjeldahl flask add 8g ammonium sulphate and 100 mL concentrated sulphuric acid. Gradually heat the mixture to boiling and boil for 10 minutes. Cool, pour the solution into 750 mL of water, and dilute to 1 L in a graduated flask 1 mL = 0.50 mg of Ti. 

If there is any doubt concerning the purity of the potassium titanyl oxalate, standardise the solution by precipitating the titanium with ammonia solution or with cupferron solution, and igniting the precipitate to TiOz. 

Titanyl Perchlorate. OTi(C104)2, mw 262.80, OB to TiO HC1 +27.4% colorl hex tablets contg an undetd number of moles of w (Ref 1). Later work indicates that the compd is probably a mixt of penta and tetra hydrates (Ref 2) Preparation. By dissolving 1 mole of anhyd Ti tetrachloride in 2 moles of anhyd perchloric ac, and the viscous yellow soin evapd in a vacuum at 30-40° to give colorl ciysts (Refs 1 2)... 

Douglas investigated heats of formation of dimethyl sulphoxide (and also of the sulphone) and proposed in a footnote that it could be determined by 5-min reaction with potassium permanganate/sulphuric acid, then adding excess iron(II) sulphate and finally titrating with permanganate. The same principle was used by Krishnan and Patel to determine dimethyl sulphoxide in various complexes (with perchlorates of titanyl, zirconyl and thorium), and by Krull and Friedmann to determine the same compound but using only dilute sulphuric acid and 5-min reaction. 

The first attempts concerned the grafting of TiCl4 and Ti(OEt)4 onto the surface of silica 145 this reaction was followed by an oxidation at 400 °C. The surface complex is presumed to be a titanyl species in which a Ti=0 2+ unit is connected to the surface by two Si — O—Ti linkages. 

Titanox FR A process for making cellulose textiles flame-resistant by treating them with titanyl acetate chloride and antimony oxychloride. Invented in 1951 by W. F. Sullivan and I. M. Panik at the National Lead Company, New York. See also Erifon. 

In the envisaged titanium oxo complex, the Ti atom is side-bound to the peroxy moiety (02H), consistent with all the spectroscopic results mentioned in Section III in Scheme 27, between the two O atoms that are side-bound to Ti4+, the O atom attached to both the Ti and H atoms is expected to be more electrophilic than the O atom attached to only the Ti atom and is likely to be the site of nucleophilic attack by the alkene double bond. The formation of the Ti-OH group (and not the titanyl, Ti=0, as proposed by Khouw et al. (221)) after the epoxidation and its subsequent condensation with Si-OH to regenerate the Ti-O-Si links had been observed (Section III.B) by FTIR spectroscopy by Lin and Frei (133). Because this is a concerted heterolytic cleavage of the 0-0 bond, high epoxide selectivity and retention of stereochemistry may be expected, as indeed has been observed experimentally (204). 

A review on the chemistry of low-valent titanium has appeared which deals with some aspects of the chemistry of titanium sulfoxide complexes (397). Titanyl complexes of the type [Ti0L5][C104]2 have... 

Cannon, K. C., Seshadri, S. R. and Dirkx, R. R., Preparation of polyesters using lithium titanyl oxalate polycondensation catalysts, EP Patent EP 0 970 983 A2 (2000). 

The quantity of hydrogen peroxide found was not equivalent to the acid sorption. Catalytic decomposition might be responsible for this. The formation of peroxide-like substances when moist air and acid reacted on carbon was deducted by Lamb and Elder (114), Kolthoff (20), and King (33) from the positive potassium iodide-starch test and, in my laboratory, from the reaction with titanyl ions. 

In the case of SHG in waveguide nonlinear crystals, we describe a theoretical model which accounts for the temporal behavior of the interacting pulses and the possible z-dependence of the phasematching condition. The model also describes the observed saturation and subsequent decrease in SHG conversion efficiency in the waveguide samples, as a result of two-photon absorption (TPA) of the second harmonic (SH) wave. The results of this model are later compared with experimental data from SHG experiments using femtosecond pulses in the waveguide nonlinear crystals of periodically-poled potassium titanyl phosphate (ppKTP) and appKTP. This model is presented in section 2.3. 

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