Acetone as solvent in flame-photometric determination of lithium in serum.
Abstract The effect of some water miscible organic solvents on the flame photometric emission of Li is discussed. A simple procedure is described with acetone as diluting solution giving a ten to twenty fold increase in sensitivity.
Micro flame photometric determination of sodium, potassium, and calcium in serum with organic solvents.
The effect of organic solvents on the flame photometric emission of certain elements in petroleum products has been reported (1). Propanol, hutanol, and acetone have been used in the flame photometric determination of sodium and potassium in serum, but these organic solvents were not used routinely, “as it was feared that complications might arise in practice owing to their volatility and to the restricted solubility of NaCl and KC1 in some solvents” (2). Apparently no extensive investigation has been made of the effect of organic solvents on the emission spectra of the cations of blood serum. We have investigated the use of organic solvents to extend the sensitivity of the flame photometer in the direct determination of sodium, potassium, and calcium, and to make practical the analyses of extremely small biological specimens. Our investigation of the effect of organic solvents on the emission spectra of sodium and potassium (3) indicated that, of the solvents studied, acetone produced the greatest enhancement of emission spectra. Less enhancement was produced by methanol, ethanol, propanol, and isopropanol in the order named. Acetone increased the spectral emission of sodium 17-fold in relative per cent transmittance and potassium 13-fold as compared with the aqueous solvent. This investigation also indicated that bovine albumin* had no effect on sodium and potassium spectra. Further study of organic solvents has been made to test their enhancement effect on the emission spectra of sodium, potassium, and especially of calcium. The use of an aqueous solvent for the direct microphotometric determination of sodium, potassium, and calcium in a single biological specimen has been reported (4).
Finite Difference Modeling on the Temperature Field of Substrate in Friction Surfacing
Friction surfacing is an advanced process of great potential, especially in the field of repair and reclamation of worn and damaged components. As a kind of thermal processing technology, the temperature profile and changes of the substrate in friction surfacing are important factors to get coatings of high quality. In this paper, the temperature field of the substrate during the process is simulated by finite difference method. The results are consistent with experiments, reappearing the temperature change of the substrate during friction surfacing, allowing further study on figuration and quality of coatings.