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Granulated iron oxide particles were incompletely reduced to structured particles comprised metallic iron and residual iron oxides. Structured particles were pressed into prismatic compacts and sintered. Some of sintered specimens were subsequently phosphatized and calcined. Specimens with an iron phosphate coating were found stiffer than specimens without coating. In Hanks' solution, a galvanic corrosion was induced by more noble iron oxides coupled to a less noble metallic iron. This could explain higher corrosion potentials and higher rates of iron dissolution in comparison with a pure iron. The coating of specimens with iron phosphates shifted corrosion potentials towards more negative values and slowed down the dissolution of iron. This was most likely caused by a reduction in oxygen flow through the coating to iron-oxide cathodes, which has enhanced the influence of diffusion control on the kinetics of reduction reaction.

Fe-Mn alloys represent promising degradable biomaterials for temporary implants. To investigate the effect of corrosion on their mechanical properties, iron powders were mixed with 25, 30 and 35 wt.% of a manganese powder, compressed into prismatic bars and sintered. Sintered bars were immersed in Hank's solution for 8 weeks. The bending stiffness of each bar before and after its exposure to electrolyte was examined. The higher the porosity of a bar was, the higher relative reduction in bending stiffness the bar exhibited. A likely explanation was that in a more porous bar Hank’s solution penetrated deeper and affected larger volume fraction of bar’s material.

Powders comprised of Fe particles and 25, 30, 35wt.% of Mn particles were mixed, compacted and sintered to investigate the effect of Mn on the properties of sintered Fe-Mn alloys. It was found that the sample’s swelling, microstructure and distribution of local hardness values were strongly affected by the Mn content. The particles in Fe-25Mn and Fe-30Mn samples exhibited a distinct onion-like structure causing a considerable variability in local properties, while the particles in Fe-35Mn samples were at a glance more homogeneous, with a large volume fraction occupied by a nearly uniform material with almost constant properties.

When the depth-sensing (nano)indentation is applied to sintered samples, measured properties, which are expected to represent the material of an individual grain, seem to depend on the overall porosity of the macroscopic sample. To understand such a result, it is assumed that while the nanoindenter penetrates into the surface grain and probes the properties of its material, the grain itself serves as another, larger indenter indenting the rest of sample and probing the properties that represent the bulk of material rather than individual grains. Load vs. displacement curve reflects the synergetic response of these two “indenters” and so it contains information about the sample’s mechanical properties at both microscopic and macroscopic scales. Obtained theoretical results agree qualitatively with the experimental data (the dependence of the indentation modulus on the porosity of sample; the indentation size effect).

The differences in mechanical properties of pressed and sintered specimens made from mixtures of iron and copper powders or from copper-coated iron powders, produced by a cementation process, were studied. For this purpose different copper contents were used (3, 8 or 12wt%) and the oxygen content of the coated powders was measured. After sintering at 1120°C for 60 minutes in hydrogen flow, microgradient structures were observed. The samples were investigated by light optical microscopy and tested under bending and tensile loads. Young´s Moduli were calculated from resonance frequencies. The copper-coating of the iron powder results in an improvement of all properties, owing to a more homogeneous copper distribution and the absence of large secondary pores, compared to specimens made from mixtures of iron and copper powders. In the case of Fe-12Cu (coated), all determined properties tend to result in a maximum: highest sintered density (7,33 g/cm³), tensile strength (489 MPa), transverse rupture strength (1098 MPa) and apparent hardness (162 HV10). The Young´s Modulus (150 GPa) of coated Fe-12Cu is nearly the same as that of sintered iron (154 GPa).

Irregular evolution of friction coefficient, recorded during the ball-on-disc test on Si3N4 based ceramic materials, was analysed by means of fractal geometry methods. Tests were carried out at room temperature, in air and without any lubricant. It was proven that the friction coefficient trace, considered as a geometric object, has the property of a fractal curve. The fractal dimension of this curve increased with increasing wear rate measured in a corresponding wear test. This could indicate the possible correlation between the wear rate and the fractal dimension of friction coefficient as a function of sliding distance (time).

The aim of this case study is to answer the question whether in the next decade and longer term the Czech Republic can participate in greenhouse gas emission trading. We analysed the position of the Czech Republic, especially with respect to one of the most discussed international agreements in this field, the Kyoto Protocol. Carbon, which is considered here primarily as the main source of energy so that it can be discussed later as the main component of greenhouse gases, is the main "binding material" of all the parts of the presented paper. The study starts with the current economic and environmental situation in the Czech Republic in its first chapter. The second part focuses on the energy sector – the main source of greenhouse gas emissions – from the point of view of fossil energy sources as well as renewable energy sources. The third chapter offers a comprehensive national greenhouse gas inventory which allows us in the following chapter to make some predictions about the Czech Republic's potential for intangible carbon flows – emission permits trading. This chapter contains projections not only for the Kyoto Protocol term (2008–2012) but also for medium (2020) and longer terms (2030). Besides the emission projections the description of possible future developments in government strategy, with respect to emission trading, has been outlined in this section. Through such a procedure the main research question, whether the Czech Republic can participate in greenhouse gas emission trading in the next decade, is answered in the affirmative for the period 2008–2012 and the potential for joint implementation and emission trading is quantified. At the end of this study we also raised some broader research questions about problems connected with the future development of an emission trading system after 2012.

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We report on point contact measurement on the heavy fermion system U2Zn17. It is shown that the first derivative of the current-voltage characteristics of low resistance contacts is very sensitive to the magnetic phase transition. The results are discussed in the frame of the heating model, which includes electrical and thermal resistivity as well as thermopower effects.