Preparation precipitation

Preparation. Precipitated siHca is formed from an alkaline metal siHcate solution, such as sodium siHcate in a ratio of approximately 2.5—3.3... 

Fig. 135. Flow chart of tantalum/niohium oxide preparation - precipitation of hydroxides by ammonia solution.

The reduction of silver chloride, precipitated in the presence of excess chloride ion, yielded the S-shaped curve typical of an autocatalyzed reaction (James, 25). The initial reaction rate, measured in terms of the reciprocal of the time required to complete 5 % of the total reaction, varied directly as the hydroxylamine concentration and inversely as the chloride ion concentration when the latter was relatively large. The specific surface of the freshly prepared precipitate, as measured by dye adsorption, decreased with aging, and the reaction rate decreased proportionately. 

Test how the prepared precipitates react with acetic or hydrochloric acids. Explain the observed phenomena. What is the composition of phosphorite, precipitate, superphosphate, and double superphosphate What are the conditions for their use in agriculture ... 

A freshly prepared precipitate of Sn02 peptised by HC1 will carry the following charge ... 

There is evidence that the Pu associated with the Zr-molyb-date precipitates is not sorbed on the solid s surface but is an integral part of the material. This is borne out by the fact that the Pu cannot be leached out of the solid phase without destroying (dissolving it) it. Also, when the freshly prepared precipitate is added to Pu(IV) solutions, Pu is not carried down (sorbed) by the Zr solid phase. 

Calcene [PPG]. TM for a specially prepared precipitated calcium carbonate for use in compounding rubber, paints, and plastics. The particles of grade TM are coated with stearic acid to aid in dispersion. Grade NC is not coated. 

Boyer s studies (B39) appear to indicate a lower degree of organ enzyme specificity than that observed by Nisselbaum et al., in that antihuman intestine alkaline phosphatase sera cross-reacted with kidney and placenta. Also, the antihuman bone preparation precipitated alkaline phosphatase from spleen, liver, kidney, and intestine. Boyer considers liver, bone, spleen, and kidney 3-phosphatases to be closely related proteins, followed by intestine and placenta, the enzyme from these latter tissues representing a second and third class of alkaline phosphatase proteins. Intestine and placenta partially cross-react with one another and with a minor kidney component. Three genetic loci are considered by Boyer, therefore, to control the synthesis of alkaline phosphatase. The most recent study in this area is reported by Birkett et al. (B19). 

Goldman711 has prepared precipitated manganese dioxide by the Attenburrow procedure as modified by Pratt and Suskind7c this material can be stored in a closed bottle and is activated, as needed, by azeotropic distillation of the excess water with benzene for about one hour. The activated reagent can be stored under benzene for more than one year. 

C under argon. Methanol was removed azeotropically at 56 °C at a fast rate and as the boiling point began to rise, the distillation rate was reduced to 4 drops/min. and heating continued for 15h. The polymer thus prepared precipitated out of cyclohexane. The powdery polymer was crystalline with a melting point (DSC) of 212 °C. It was insoluble in the usual organic solvents such as methylene chloride, chloroform, ether, tetrahydrofuran, ethyl acetate, acetone, dimethylformamide, and dimethylsulfoxide. 

How to prepare standard acid and base solutions, pp. 43, 44 Common laboratory apparatus for handling and treating samples, p. 44 How to filter and prepare precipitates for gravimetric analysis, p. 48 How to sample solids, hquids, and gases, p. 52 9 How to prepare a solution of the analyte, p. 53... 

Sample preparation Precipitate proteins with MeCN containing cefotetan. 

To compare the optical density of nanocomposite suspension in polycarbonate solution in ethylene dichloride, as well as polycarbonate and polycarbonate samples modified with nanocomposites, spectrophotometer KFK-3-Ola was used. Samples in the form of modified and non-modified films for studying IR spectra were prepared precipitating them Ifom suspension or solution under vacuum. The obtained films about 100 mcm thick were examined on Fourier-spectrometer FSM 1201.To investigate the crystallization and stmctures formed the high-resolution microscope (up to 10 mcm) was used. 

Bomal, Y, Chevallier, Y, Cochet, P., 1995. Novel method for preparing precipitated silica, novel aluminium-containing precipitated sihcas, and use thereof for reinforcing elastomers. Patent W09630303. 

Sample preparation Precipitate proteins with MeCN and perchloric acid, ii ject an aliquot. 

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