Lanthanum acetate

Modification by acetylacetone is a powerful route, that allows precursor solutions to be stabilized. Interaction of titanium alkoxides with acetylacetone was extensively studied and reviewed in [1391,86]. Study ofreactions, occurring on interaction of Zr(OPrn)4 and Ti-Zr alkoxide mixture with acetylacetone, was performed in [1448] and allowed the authors to simplify the technique for preparation of precursor solution for PZT films application and to overcome the requirement of prolonged refluxing, which certainly decreases reproducibility. After dissolution of titanium and zirconium alkoxides in methoxyethanol, acetylacetone is added to form stable zirconium and titanium stock solutions. The introduction of acetylacetone allowed aqueous lead acetate (and lanthanum acetate for PLZT films) solutions to be added to mixed titanium and zirconium solutions. No reaction steps involving elevated temperatures or distillation or long reaction times are required. The solution could be used both immediately on mixing or after storage for several months. Such solutions were successfully used for application of ferroelectric films. 

Lanthanum nitrate test Treat 0-5 ml of the acetate solution with 0-5 ml OTm lanthanum nitrate solution, add 0-5 ml iodine solution and a few drops of dilute ammonia solution, and heat slowly to the boiling point. A blue colour is produced this is probably due to the adsorption of the iodine by the basic lanthanum acetate. This reaction provides an extremely sensitive test for an acetate. 

Lu et al. prepared dense ceramic fibers of PbixLa,Ti03 (PLT, x = 0-0.2) by a sol-gel method from lead acetate trihydrate, lanthanum acetate, and titanium isopropoxide in triethanolamine and acetic acid, followed by solvothermal treatment in a mixture of xylene and triethylamine at 200°C for 12 h. They reported... 

This method makes use of commercially available, thin-layer plates coated with a cation-exchange resin in the sodium form the sodium ions can readily be exchanged for other cations by immersing the plate in an appropriate salt solution. Cupric, calcium, and lanthanum acetates have been used to introduce cations that complex readily. The plate is then developed with water as the irrigant. Compounds that form complexes with the cations are retained and have low values those that complex weakly are... 

The supports used were a Y-AI2O3 with a BET area of 100 m /g and the same alumina modified by addition of lanthanum acetate in order to obtain an Al203-La203 support with 12 wt % lanthanum oxide after calcination at 500°C. The alumina support is initially ground... 

Lanthanum acetate + acridine orange in acetic acid DNA, RNA-orange red... 

In our case, Lao,66Sro,33Mn03 was prepared with lanthanum nitrate, lanthanum acetate and lanthanum chloride. After dissolution in water, they were mixed with manganese acetate and strontium nitrate, and then stirred for half an hour. A gel formed after addition of citric acid which protonates the ligands. Ethylene glycol was used for esterification and to improve solubility. Finally ammonium hydroxide was added for peptization, followed by stirring for 1 h. 

If novolac is produced with lanthanum acetate or Zn oxide as catalyst, or-thonovolacs are obtained in the main, in which the content of o-, o -methylene bridges is as high as 45-50% while m-, m -methylene bridges do not exceed 5%. Also interesting is that the condensation process without catalyst at pH = 4-5 yields a significant amount of o-, o - and o-, p-dihydroxydiphenylmethane in these products, p-, p -isomer is lacking. 

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