Sum ma rySamples of five soils whose pH in the field had been adjusted to between 5.0 and 7.5 were incubated with water or 0.01 M CaC12 at 90% field capacity. Additional samples of the most acid soil were limed to various pH values immediately before incubation.Manganese, zinc and cobalt concentrations in the soil solutions, collected by displacement, decreased as the pH increased; the concentrations in calcium chloride solutions were higher than those in water solutions. The free divalent ions Mn2+, Zn2+ and Co2+ were the major metal species in solution at pH 5 but the proportion of the metals present as the free ion decreased as the pH increased.Differences in the manganese and zinc concentrations in the solutions were due not only to the pH of these solutions but also to the original pH of the soil in the field.

not Available.

No abstract

The Schiff-base dianion N,N'-2,2-dimethyltrimethylenebis[salicylideneiminate(2-)] (salnptn) coordinates to vanadium( w ) to form [VO(salnptn)] whose crystal structure has been determined. The compound is polymeric in the solid state with -. V=O ---V=O -+ V=O chains, the salnptn donor atoms being coplanar and the salnptn framework umbrella-shaped. In the derivative [VO(OMe)(salnptn)], the crystal structure of which has also been determined, the OMe and the vanadyl oxygen are co-ordinated cis to each other, and the salnptn now occupies three equatorial and one axial coordination positions. Even N,N'-ethylenebis(salicy1ideneiminate) seems to behave analogously, though it is normally planar.We have recently described a series of vanadium(1v) complexes of tetradentate dianionic Schiff bases.' It is now well established that vanadyl(rv) compounds with such ligands are essentially five-co-ordinate, but they fall into two classes, one of green compounds with v(V=O) ca. 980 cm-' in which the five-coordinate species are without obvious intermolecular interactions in the crystal, and another which are yellow-brown, with v(V=O) ca. 880 cm-l and which appear to 'polymerise' in the crystal, forming V=O --+ V=O --V=O chains, though the 0 -V co-ordinate bond is rather long, ca. 2.2 8, compared with ca. 1.6 8, for V=0.2 Among the compounds we prepared was wO(2-OC6H4-CH=NCH,CMe2CH2N=CHC6H40-2)] ' or wO(salnptn)] which shows v(V=O) at 871 cm-' and is orange, suggesting a polymeric structure in the solid, but its solubility in organic solvents is nevertheless very high. Accordingly we undertook an X-ray crystal-structure analysis to determine whether the colour and IR data, or the solubility, is the more reliable indicator of the solid-state configuration.

The solid‐liquid phase diagram, experimental glass transition points, densities, viscosities, and electrical conductivities of the aluminum bromide‐1‐methyl‐3‐ethylimidazolium bromide ionic liquid are reported. Certain compositions of this two‐component molten salt are liquid at room temperature. Density, viscosity, and conductivity data were collected over the range of aluminum bromide mole fractions from ca. 0.35 to 0.75 and over the range of temperatures from ca. 25° to 100°C. Equations are presented that describe both the composition and temperature dependence of the densities and transport properties. Both the viscosities and the conductivities display the non‐Arrhenius temperature dependence typically associated with glass forming ionic liquids. Temperature‐dependent activation energies are derived for these transport processes by using the Vogel‐Tammann‐Fulcher equation.