Nitrogen metabolism and kidney function of the dik-dik antelope (Rhynchotragus kirkii) were studied under a range of controlled, experimental conditions and diets. Dik-dik antelope remained in nitrogen balance even when fed a diet low in protein and high in fibre. When fed a diet high in protein (20%) and water ad-libitum, 55.3% of the urea filtered by the kidney was reabsorbed. Limiting water ...

Ion association of the ionic liquid [bmim][Cl] in acetonitrile and in water was studied by dielectric spectroscopy for salt concentrations c r 1.3 M at 298.15 K and by measurement of molar electrical conductivities, L, of dilute solutions (c r 0.006 M) in the temperature range 273.15 t T/K r 313.15. Whilst acetonitrile solutions of [bmim][Cl] exhibit moderate ion pairing, with an association co...

In the present work the dehydration process of layered solids with formula unit M(H₂O)₂[Ni(CN)₄]·nH₂O, M = Ni, Co, Mn; n = 1, 2, 4 is studied using modulated thermogravimetry. The results show that water molecules need to overcome an energetic barrier (activation energy between 63 and 500 kJ/mol) in order to diffuse through the interlayer region. The related kinetic parameters show a dependence...

Ion association of the ionic liquid [bmim][Cl] in acetonitrile and in water was studied by dielectric spectroscopy for salt concentrations c ≤ 1.3 M at 298.15 K and by measurement of molar electrical conductivities, Λ, of dilute solutions (c ≤ 0.006 M) in the temperature range 273.15 ≲ T/K ≤ 313.15. Whilst acetonitrile solutions of [bmim][Cl] exhibit moderate ion pairing, with an association co...

Accurate estimation of soil water retention curve (SWRC) at the dry region is required to describe the relation between soil water content and matric suction from saturation to oven dryness. In this study, the extrapolative capability of two models for predicting the complete SWRC from limited ranges of soil water retention data was evaluated. When the model parameters were obtained from SWRC d...

We can recover genetic information from organisms of all kinds using environmental sampling. In recent years, sequencing this environmental DNA (eDNA) has become a tractable means of surveying many species using water, air, or soil samples. The technique is beginning to become a core tool for ecologists, environmental scientists, and biologists of many kinds, but the temporal resolution of eDNA...

Two different fractions of manganese were found in the maize plant root apoplasm (intercellular space containing cell walls) after soaking the roots in MnCl2 solutions (concentration range 0.01-10 mmol.l-1): (a) an Mn2+ fraction in the water free space (WFS) which gave a characteristic six-line spectrum, and (b) an immobilized fraction that gave no detectable ESR spectrum. Both fractions affect...

Concepts of the modified and the excess Walden products are introduced and discussed when applied together with the ordinary Walden product. The existence of the universal curves of limiting conductances for electrolytes (or for ions) in a given pair of solvents are further examined for a number of mixtures which include ethanol, 2-propanol, 1,1,1,3,3,3hexafluoro-2-propanol, N,N,-dimethylformam...