The densities of the binary solutions Nad-H20, KCI-H20, MgClj-HjO, and CaCI2-H20 were measured at 1 atm, from 25 to 45 °C and from 0.5 to 6.1 m, by using a commercially available oscillating tube-type densitometer. The data sets were described by using least-squares polynomial regression analysis. Statistical evaluation of the experimental data Indicates that uncertainties In the concentrations of the solutions due to adsorption of water by the salts during weighing Is the major source of error In the density measurements. The magnitude of this error Is greater for MgCI2 and CaCI2 solutions because of the hygroscopic nature of these salts. The measured densities of NaCI and KCI solutions have a standard deviation of 5.515 X 10~3 g/cm3. Standard deviations for MgCI2 and CaCI2 solutions range from 2.329 X 10~4 to 2.334 X 10"4 g/cm3 and from 2.796 X 10'4 to 2.839 X 1CT4 g/cm3, respectively. The experimental density data compare well with published values.

No abstract

Solubility relations In the CeCI-rlch region of the ternary system NaCI-CsCI-H20 have been determined at 25 °C by using the Isothermal method. These data together with the halite solubility data reported In part 1 of this series complete the solubility relations for the entire ternary system at 25 °C. A new compound, ß •2 ß •2 20, and a new solid-solution series, [Cs^tNa-H^jjCI with x ranging from 0 to 0.427, were found In this study. The new compound Is monocllnlc, belongs to space group /2/c, and has a = 13.620 (2), b = 5.831 (1), c = 10.709 (2) A, ß = 91.27 (1)°, Z = 4, V = 850.3 (1) A3;refractive Indices are = 1.520, ß = 1.540, = 1.552; density Dx = 2.509 g/cm3. The solid solution is cubic with the cell edge slightly larger than that of CsCI and the refractive index ntsD = -0.14638* + 1.8405.

It is known that macromolecular organic matter in aquatic environments, i.e., humic substances, is highly aliphatic. These aliphatic macromolecules, predominantly paraffinic in structure, are prevalent in marine and lacustrine sediments and are believed to originate from algae or bacteria. A comparative study of mixed and pure cultures of green algae and their decomposed residues was performed by using solid-state 13C nuclear magnetic resonance spectroscopy as the primary analytical method. Results obtained in this study confirm the presence of components that are chemically refractory and that are defined as alghumin and hydrolyzed alghumin. These were detected in heterogeneous, homogeneous, and axenic biomasses composed of several genera of Chlorophyta. Although the chemical composition of algal biomass varied with culture conditions, the chemical structure of the alghumin and hydrolyzed alghumin, demonstrated by '3C nuclear magnetic resonance spectroscopy appeared to be constant for members of the Chlorophyta examined in this study. The