Potassium, compressibility

Infrared spectra for solid organic compounds are frequently obtained by mixing and grinding a small sample of the material with specially dry and pure potassi um bromide (the carrier), then compressing the powder in a special metal die under a pressure of 15 30 tonnes to produce a transparent potassium bromide disc. As the potassium bromide has virtually no absorption in the middle-infrared region, a very well-resolved spectrum of the organic compound is obtained when the disc is placed in the path of the infrared beam. 

In theory, increased quantities of the organic compound finely ground with constant quantities of potassium bromide should give infrared spectra of increasing intensity. However, good quantitative results by this direct procedure are difficult to obtain due to problems associated with the non-quantitative transfer of powder from the small ball-mill grinder (or pestle and mortar) into the compression die. These are only partially overcome by using a micrometer to measure the final disc thickness. 

Diaikanol aminoalkyl phenols as admixtures enhance the strength [675]. The additives are useful in very small amounts and do not affect the initial properties of the fluid. The strength additive does not cause set acceleration or early set strength enhancement but provides enhanced compressive strength of the cement in later stages. Addition of small amounts of potassium ferricyanide and nitrile-trimethyl phosphonic acid promotes the formation of complex compounds and thus increases the strength of cement rock [1771]. 

Dining its preparation, solutions of the salt, which is a dangerous detonator, must not be evaporated to dryness. Surprisingly, mixtures with potassium bromide could be compressed (for IR examination) to 815 bar without decomposition. It contains 71% of nitrogen. 

Figure 4. Recompression effects on PhDA2-8 jc-A curves over a subphase containing both cadmium chloride and potassium bicarbonate. The subphase temperature 5.0°C and the compression rate was 7.5 (A2/molecule)/min. For recompiession the blade was stopped at each of the following the surface pressures ...

Brown and coworkers (17-18,47) reported compositions of dusts from cotton compresses and warehouses. Samples were removed with the aid of a sonic bath in hexane. The compresses were in Mississippi, Southeastern and Western Texas, and New Mexico. The samples in the bale press area were high in ash content with silicon the most abundant element (up to 18.7% in one New Mexico compress Scimple). Compared with card room dusts, samples from compresses were high in aluminum, silicon, chlorine, iron and magnesium and relatively low in potassium, phosphorus and zinc. The ratio of silica to silicon was high also for these scunples compared with textile mill dusts. 

Hayduk, W. and Laudie, H. "Vinyl chloride gas compressibility and solubility in water and aqueous potassium laurate solutions, J. Chem. Eng. Data, 19(3) 253-257, 1974a. 

The submitters dried the ethylamine and pyridine by distillation over potassium hydroxide pellets. The submitters used 600 ml. of petroleum ether, 113 g. (2.50 moles) of ethyl-amine, and 158 g. (2.00 moles) of pyridine to which was added 135 g. (1.00 mole) of sulfuryl chloride in 250 ml. of petroleum ether. In the United States ethylamine is sold in 100-g. quantities in sealed-glass vials (Eastman Organic Chemicals) or as the compressed gas in cylinders (Matheson Gas Products). The checkers used the contents of a freshly opened vial (without distillation) for each run as a matter of convenience. The checkers used either ])entane or petrolonm eth(M (b.p. 38-51°). 

Patients at greatest risk for developing potassium chloride-induced Gl lesions include The elderly, the immobile and those with scleroderma, diabetes mellitus, mitral valve replacement, cardiomegaly, or esophageal stricture/compression. 

The distortions of the NbFe-octahedra affect the 8-coordination about the potassium ions and give it an irregular shape, which may be seen as the combination of two tetrahedra, one of which is compressed (K—F = 2.59 A), the other elongated (K—F = 2.95 A) along the 4-fould axis of KNbFg. Because of the very great distance (3.63 A) of 4 additional... 

In 1808 Sir Humphry Davy tried in vain to decompose zirconia with the electric current, but Berzelius (36) finally obtained the metal in 1824 by heating a dry mixture of potassium and potassium zirconium fluoride in a very small closed iron tube placed inside a platinum crucible. After the quiet reaction had taken place, he cooled the tube and placed it in distilled water, whereupon, to use his own words, There fell from the tube a black powder as fast as the salt dissolved, and at the same time there was evolved a small quantity of hydrogen.. . . The zirconium obtained in this manner is easily deposited. It can be washed with water without oxidizing. Washed and dried, it forms a black powder resembling charcoal, which cannot be compressed nor polished like a metal (15). 

Forms fluorides with most elements, except the inert gases. Occurs widely distributed to the extent 0.03% of the earth crust. The chief minerals are fluorapatite cryolite and fluorspar. Can be obtd by electrolysis of molten anhydrous hydrofluoric acid-potassium fluoride melts with special Co-bearing carbon anodes, steel cathodes containers and monel screens. Available in special steel cylinders, both as a liquid and as compressed gas... 

In this study, the influence of several formulation factors on the release kinetics of potassium chloride from directly compressed matrices is investigated. Formulations containing hydrophilic (methylcellulose, carbomer), plastic (polyvinyl chloride) and wax (glycerol palmitostearate) matrix materials at concentrations of 10%, 15% and 20%, and insoluble excipients, were prepared and tested using the USP XXI-NF XVI rotating paddle method. 

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