Preparation of strong ammonia solutionSCHMIDT JOSEF DR.
Hydroxylammonium salt solution prepared by catalytically reducing nitrate ions in aqueous solution using molecular hydrogen in a buffered reaction medium containing at least twice the number of sulphate ions as phosphate ions in which the ammonia produced as a by-product of the reaction is removed fro...
After the TEOS solution is added into the aqueous solution, most of the TEOS is decomposed into silicic acid (Si(OH)4), which is an important silica-forming monomer. The silica monomers coalesce, condense, and polymerize to form nuclei. The nucleus is the smallest size of silica, which has...
Using tetraethyl orthosilicate(TEOS)as silica source and ammonia as catalyst,while varying the initial surfactant,different spherical mesoporous silica were synthesized in alkali condition .The particles were characterized using transmission electron microscopy(TEM).Using a charged template,cetyltrimethylammonium...
Preparation and Performance of the Catalyst for the Synthesis of Methyl Chloride from Ammonia Chloride and Methanol The catalysts for the synthesis of methyl chloride from ammonium chloride and methanol were prepared with equal-volume impregnation method,using γ-Al2O3 a... Y Sun,S Liu,J Shang,...
of formula I or the corresponding N-oxide: in which the pentapyranose group is D- or L-5-thioxylopyranose and R, R1 and R2 are as defined in the starting compounds; b) if necessary, reacting the compound of formula I obtained above with a solution of ammonia in methanol to give the...
For example, the Stober process allows the synthesis of mono-dispersed silica nanoparticles. This process involves hydrolysis and condensation reactions in an alcoholic solution in presence of ammonia as a catalyst. The increase in silica precursor or ammonia concentrations leads to the increase in ...
Copolymer of acrylamide and ammonium acrylate was prepared by inverse emulsion polymerization,with liquid paraffin as continuous phase,acrylic acid and acrylamide aqueous solution as dispersing phase,N,N′-methylene-bisacrylamide as cross-linking agent,Span-80 and Tween-80 as complex emulsifier,and ammon...
·9H2O, anhydrous aluminum chloride (AlCl3) and ammonia solution (35%). The commercial γ-Al2O3(BET = 117 m2g−1) was supplied from Alfa Aesar, used after crushing the pellets in particle size of 250–425 µm, designated as γ-Al2O3and was used without any further ...
preferably an oxalate salt followed by conversion to free base by treatment with a suitable base. Eletriptan oxalate is the most preferred salt and the most suitable base is selected from the group comprising NaOH, KOH, Na2CO3, K2CO3, ammonia solution / NH4OH. Eletriptan free base thus obtained...