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Interfacial rheological properties of different Hungarian crude oil/water systems were determined in wide temperature and shear rate range and in the presence of ethoxylated nonyl-phenols with ethoxy group number between 10 and 40. The fundamental conclusion of the experimental results is that the interfacial viscosity, the non-Newtonian flow behavior and the activation energy of the viscous flow drastically decrease in the presence of non-ionic surfactants. Modification of these interfacial rheological properties increase with decreasing ethoxy group number and increasing tenside concentration and temperature. The most radical change was observed in the presence of NPEO10. As a summary it was evidenced that the interfacial rheology is an efficient and powerful detection technique, which may enhance our knowledge on formation, structure, properties and behavior of interfacial layers formed in oil/water systems. Thus, similar studies will probably accelerate the progress significantly not only in oil recovery but also in all areas of colloid science and technology. [ABSTRACT FROM AUTHOR]

The micelle formation of ethoxylated nonyl-phenols in the presence of short-chain alcohols was investigated within a temperature range of 293-333 K. On the basis of the actual CMC values and their temperature dependence the thermodynamic functions of micelle formation (ΔHm0, ΔSm0, ΔGm0) and the thermodynamic functions of transfer of surfactant from pure aqueous phase to water-alcohol mixtures (ΔHtr0, ΔStr0, ΔGtr0) were also calculated. According to the experimental results the set of optimum conditions leading to the formation of a micellar structure with satisfactory stability can be determined. In the three-component systems the more stable the structure of micelles formed, the higher the temperature, the longer the alcohol chain length, the lower the alcohol content, and the shorter the poly-oxyethylene chain of monomers. With respect to the practical EOR process, it may be stated that the addition of alcohols to the solutions of short-chain nonyl-phenols makes it possible to extend their application to hydrocarbon reservoirs having high formation temperature. [ABSTRACT FROM AUTHOR]

Chapter 6 of the book "Stable Isotopes as Indicators of Ecological Change," by Michael Lakatos, Britta Hartard, and Cristina Máguas, is presented. It highlights the unique characteristics of lichens as well as its cosmopolitan distribution, and its vulnerable role to a wide range of environmental changes, with natural and human origin. It evaluates the ecological value of poikilohydric lichens that substantially differ from homoiohydric vascular plants.

57Fe conversion electron Mössbauer spectroscopy, X-ray diffraction, electrochemical and magnetic measurements were used to study pulse electroplated Fe-P and Ni-Fe coatings. XRD and 57Fe CEMS measurements revealed the amorphous character of the novel pulse plated Fe-P alloys. CEM spectra indicated significant differences in the short range order and in the magnetic anisotropy between the Fe-P deposits pulse plated at medium long deposition time (ton=2 ms), with short relaxation time (toff=9 ms) and low current density (Ip=0.05 Acm−2) or at short deposition time (ton=1 ms) with long relaxation time (toff=250 ms) and high current density (Ip=1.0 Acm−2). The broad peaks centred around the fcc reflections in XRD of the pulse plated Ni-22 wt.% Fe deposit reflected a microcrystalline Ni-Fe alloy with a very fine, 5-8 nm, grain size. The CEM spectrum of the pulse plated Ni-22 wt.% Fe coating corresponded to a highly disordered solid solution alloy containing a minute amount of ferrihydrite. Extreme favourable soft magnetic properties were observed with these Ni-Fe and Fe-P pulse plated thin layers. [ABSTRACT FROM AUTHOR]