Character of Pb~(2+) absorption on natural iron-(hydr)oxide minerals
This paper tries to study the absorption behavior of copper (Ⅱ) on natural iron-(hydr)oxide minerals, and the characters are summarized as follows. (1) Different minerals clearly have different absorption abilities. To the same kind mineral, kinds and contents of impurity are the main effect factors to absorption ability, and the crystal habit affects its absorption ability slightly. (2) The effect of mineral size on absorption ability changes irregularly when the size is larger than 140 mesh. (3) pH affects absorption ability dramatically. (4) The absorption amount is correlated with initial concentration of copper (Ⅱ) positively. (5) The absorb behavior of copper (Ⅱ) on natural iron-(hydr)oxide minerals is apparent agreement with Freundlich iso-temperature absorption.
The paper deals with the example of application of the two continuum rheological model of materials with microdefects, nanodefects and solute hydrogen for calculation of stress and strain in cylindrical specimen under periodic loading. The model suggested allows one to relate the mechanical characteristics with the hydrogen concentration.The stability analysis of the system metal-hydrogen is carried out. The influence of parameters of the mechanical loading, hydrogen concentration and parameters of sorption and desorption of hydrogen from the surface of the internal defects (traps) of various nature on the system stability is performed.It is shown that influence of hydrogen can be considered as parametric instability of a continuous medium under mechanical deformation.This can be important during forming or plastic deformation of materials and nanomaterials containing hydrogen.