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The temperatures ductility of the polycrystalline Ni 2.19 Fe 0.04 Mn 0.77 Ga alloy was investigated. The analysis of the temperature dependence of the specific magnetization shows that temperatures of the martensitic and magnetic phase transformations have the following values: M F =325 K, A S =343 K, T C =365 K. The differential scanning calorimetry shows that in the temperature range of 930 to 1070 K in the alloy the phase transition of the ordered L2 1 phase to disordered B2 phase is observed. The stress-strain curves of cylindrical samples of alloy at temperatures of 773 K, 873 K and 973 K were constructed.

Heusler alloys demonstrate various effects, such as the ferromagnetic shape memory effect, the magnetocaloric effect, etc. But these alloys are also liable to destruction during multiple cycles of martensitic transformation. In order to increase stability of functional properties of the alloys, thermo-mechanical treatment by various methods is carried out. In this work, a Heusler Ni2.26Mn0.80Ga0.89Si0.05 alloy was subjected to combined deformation processing: multiple isothermal forging and subsequent direct extrusion. The multiple isothermal forging was carried out at 700 °C in 5 upset transitions and a total true degree of deformation of e ≈ 2.42. The extrusion was also carried out at 700 °C with an extrusion ratio of 2:1 (e = 1.39). Analysis of the microstructure shows that, resulting from combined treatment, metallographic and crystallographic textures are formed. The metallographic texture is characterized by coarse grains of approximately 1 mm in length and hundreds of microns in diameter. The coarse grains are in turn surrounded by a layer of fine-grained structure. The crystallographic texture is axial of the 〈1 1 0〉 type. This kind of structure enhances mechanical properties of the alloy. According to the study of thermal expansion anisotropy in the region of martensitic transformation, contribution of the martensitic transformation to the relative change in the length of the extruded sample is 0.13% in the direction, normal to the extrusion axis, and 0.09% - along it. These values are comparable to those observed on Heusler alloys in the as-cast state. Thus, it is found that thermo-mechanical treatment by the combined method allows obtaining a significant amount of thermal expansion anisotropy while remarkably increasing mechanical properties of the material.

Hybrid-silica materials containing octyl, phenyl and urea-propyl functional groups were reported. These functionalized silicas were prepared by a via one-pot synthesis method through co-condensation of tetraethyl ortosilicate with organosilanes co-precursors. The obtained materials were analyzed by a number of techniques including scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction pattern and nitrogen sorption measurement. The main elements: morphology and surface properties of the final products that are basically dependent on the type and the quantity of functional-containing groups were fully discussed. The adsorption properties of the modified silicas were investigated against bilirubin in aqueous solution at pH 7.4, the effect of time was studied as well. The modified silicas showed a greatly increasing of adsorption capacity for bilirubin compared to pure amorphous silica. The results indicate that the type of functional-containing groups and surface properties affect the adsorption behavior. These materials show a potential application as effective adsorbents for bilirubin removal.