Barium pyrophosphate

Ba207P2 barium pyrophosphate 13466-21-2 25.00 3.9000 1 725 CaCrH406 calcium chromate dihydrate 13765-19-0 25.00 2.5000 1... 

Hrat 259 nm and pH 7-0. Freely sol in water- A % aq soln has a pH of about 2 and is stable at 0 for several hrs-ATP is a tetrabasic acid and after hydrolytic cleavage it is hexabasic. It is usually pptd as the dibarium salt with 4 or 6 mols of water of crystn which can be removed by prolonged drying at 100° over PjOj and in a vacuum. The anhydr salt is stable, but the hydrated salt slowly decomp forming 5 -adenylic acid and barium pyrophosphate, For use the hari-um salt is converted to the sodium or potassium salt by treatment with sodium or potassium sulfate in HCl soln. At pH 6,8 -7,4 the Na salt is stable hi aq soln provided ihe product is pure. Ba2+ catalyzes breakdown. Injectable solns of the disodium salt are marketed as Triftoffm, Adei phos Circttlen "Kyorin Atenen. 

AnalaR glacial acetic acid and tetra-sodium pyrophosphate decahydrate were from BDH. Chemicals/reagents from Aldrich acetonitrile, anhydrous 1,4-dioxane (dioxan), barium 2-cyanoethylphosphate hydrate, 2,4,6-collidine (99%), anhydrous DMF, phosphoryl chloride (phosphorus oxychloride) (99 and 99.999%), thiophosphoryl chloride (98%), salicyl chlorophosphite (2-chloro-4//-l,3,2-benzodioxaphosphorin-4-one), tri-n-butylamine (99+%), triethylamine (99%), tri-n-octylamine (99+%), trimethylphosphate (99+%), 3 A molecular sieves. 

Another example is in the separation of sulfate or phosphate from various cations. Samuelson devised a method for sulfur in pyrites that is based on the retention of iron(m) on a cation-exchange resin. The sulfuric add that passes through the colunm can be determined by the usual gravimetric method as barium sulfate. In a similar way, phosphate in phosphate rock can be determined by retention of calcium, magnesium, iron, and aluminum on a cation-exchange resin followed by deterlnination of the phosphate as magnesium pyrophosphate. The metal ions can be eluted from the column with 4 M hydrochloric acid. 

The variety of substances used as additives in polymers is considerable. For example, the fillers may include china clay, various forms of calcium carbonate, talc, silicas (diatomaceous silica), silicates, carbon black, etc. The impact modifiers typically include other polymers. Plasticizers include certain polymers with low (oligomers), dialkyl phthalates, dialkyl sebacates, chlorinated paraffin waxes, liquid paraffinic fractions, oil extracts, etc. Heat stabilizers include heavy metals salts such as basic lead carbonate, basic lead sulfate, dibasic lead phosphite (also acting as a light stabilizer), dibasic lead phthalate, stearates, ricinoleates, palmitates and octanoates of cadmium and barium, epoxide resins and oils, amines, diphenylurea, 2-phenylindole, aminocrotonates. The antioxidants include tris-nonyl phenyl phosphite, 2,6-di-ferf-butyl-p-cresol (BHT), octadecyl-3,5-di-terf-butyl-4-hydroxyhydrocinnamate, etc. The UV stabilizers include modified benzophenones and benzotriazoles. Processing lubricants include calcium stearate, stearic acid, lead stearate, various wax derivatives, glyceryl esters and long-chain acids. Fire retardants include antimony oxide, some pyrophosphates, etc. 

The nucleotide anhydride, adenosine 5 -triphosphate (24), when digested with aqueous barium hydroxide, gives a complex mixture containing such products as adenine, adenosine, adenosine 2 -, 3 -, and 5 -phosphates, adenosine 5 -pyrophosphate, and adenosine 2 (or 3 ),5 -diphosphate. - In addition, a nucleotide was foimd in this digest whose structure proved - to be that of adenosine 3 5 -cyclic phosphate (25). This component did not consume metaperiodate, and was degraded enzymically to adenosine 5 -phosphate (26) and adenosine 3 -phosphate (27), without the formation of adenosine 2 -phosphate. Hydrolysis of (25) with an acidic ion-exchange resin did, however, produce the 2 - and 3 -phosphates of adenosine. Compound (25) possessed only one phosphoryl dissociation, and showed a ratio of nucleoside to phosphate of 1 1, which, along with a molecular-... 

Barium and strontium pyrophosphates will yield phosphorescent materials (Chapter 12.20), for example, Sr2P207 doped with Sn produces blue and Ba2P207 doped with Ti produces bluish white. 

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