Cesium chloride technique

The distribution of N and N was revealed by the technique of density-gradient equilibrium sedimentation. A small amount of DNA was dissolved in a concentrated solution of cesium chloride having a density close to that of the DNA (1.7 g This solution was centrifuged until it was nearly... 

For trace determinations of cesium cations the procedure is executed in two steps First, 3 /il of a standard solution containing a known amount of cesium chloride is applied to the emitter by means of the modified syringe technique s and a signal at m/z 133 is recorded. S nd, between 0.2 pA and 1 1 of sample are applied to the same emitter and desorbed under identical conditions. From the peak areas of the evaporation profiles obtained in both measurements, the unknown amount of the alkali element present in the sample is calculated. Usually, one analysis (calibration + sample analysis) can be performed within 30 min. Thus, cesium in sample sizes of 0.2 to 1 jul, which contain 0.3 to 1000 pg of the element, can be determined. The accuracy of repeated measurements of a standard solution is 10% and that of the technique for the determination of unknown concentrations 20 %. A sensitivity between 1.4 and 2.5 X 10 C per g is obtained for cesium. Since a good sensitivity value for an organic FD ion, namely the molecular ion of cyclophosphamide, has been reported to be 1 to 2X 10 C per it is clear that FDMS is about a factor of 100 more sensitive for the [Cs] ion. 

Abstract - The standard potentials of the reaction steps for the reduction of TiCLi in alkali chlorides were calculated from transient electrochemical techniques. It is shown that the stability ranges of the various oxidation states of titanium depend on the composition and temperature of the solvent. The presence of strong chloride ion donors, such as cesium chloride, enhances the stability of the high oxidation states. The results are interpreted in terms of formation of chlorocomplexes. The thermodynamic properties of solutes were calculated and the Gibbs energy of dissolution of the titanium salts determined. 

During the processing of pollucite the ground mineral is dissolved and silica and alumina are removed from the solution. Salts of alkali metals are present in the filtrate. The separation of these was once very time consuming, as it had to be done with fractional crystalHzation. Nowadays an ion-exchange technique is used, which makes the separation fast and simple. Cesium hydroxide is prepared from the pure cesium solution, and is the base for cesium chloride, iodide, carbonate and other compounds. Cesium metal is prepared by reduction of cesium chloride with calcium metal. 

During the search for 36C1 at Rochester, 5-13 pA of Cl ions were produced from silver chloride in the cesium sputter source. The detection techniques were basically similar to those discussed for 14C. The samples and the results obtained are given in Table 2. 

Bunsen is remembered chiefly for his invention of die laboratory burner umned after him. He engaged in a wide range of industrial and chemical research, including blast-furnace firing, electrolytic cells, separation of metals by electric current, spectroscopic techniques (with Kirchhoff). and production of light metals by electrical decomposition of their molten chlorides. He also discovered two elements, rubidium and cesium. 

Electrochemical techniques have often been used to study the thermodynamics of solutions. The present study shows that the oxidation of titanium ions in fused alkali chlorides depends dramatically on the composition of the melt. Large cations weakly bonded to chloride ions, such as cesium ions, promote the formation of titanium hexachlorocomplexes, TiCl or TiCl , and results in a large stability range for the high oxidation states. Ti " reduces directly to metallic titanium. This behaviour is similar to that obtained with stronger ligands such as fluoride ions [9, 22]. 

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