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We report on modifications of 280-nm thin polycrystalline CrN layers caused by vanadium ion implantation. The CrN layers were deposited at 150°C by d.c. reactive sputtering on Si(100) wafers and then implanted at room temperature with 80-keV V+ ions to fluences of 1×1017 and 2×1017 ions/cm2. Rutherford backscattering spectroscopy, cross-sectional transmission electron microscopy, and X-ray diffraction were used to characterize changes in the structural properties of the films. Their optical and electrical properties were analyzed by infrared spectroscopy in reflection mode and electrical resistivity measurements. CrN was found to keep its cubic structure under the conditions of vanadium ion implantation used here. The initially partially non-metallic CrN layer displays metallic character under implantation, which may be related to the possible formation of Cr1−x V x N. [ABSTRACT FROM AUTHOR]

Silicide formation and ion beam mixing of Fe/Si bilayers due to Ar-, Xe- and Au-ion irradiations at room and liquid-nitrogen temperatures were investigated. For the study of silicide phase formation, the Fe/Si bilayers were irradiated with 100-keV Ar[SUP+], 250-keV Xe[SUP+], 700-keV Xe[SUP2+] or 400-keV Au[SUP+] ions at fluences of 1 × 10[SUP15] to 2 × 10[SUP16] ions/cm[SUP2]. The influence of the ion-charge state on the mixing process was studied in Fe/Si by 100-keV Ar[SUP8+]-ion implantation, in addition to the corresponding irradiations with singly charged ions at the same energy. Changes in the samples were analyzed by Rutherford backscattering spectroscopy, conversion electron Mössbauer spectroscopy, X-ray diffraction and atomic force microscopy. Pronounced structural changes and the intermixing of the components at the Fe/Si interfaces were measured as a function of the ion species, ion fluence and sample temperature. A linear correlation between the interface broadening and the fluence was observed for all the cases. Mössbauer analysis with enriched [SUP57]Fe layers revealed the onset of phase formation out of the solid solution. In order to interpret the mixing rates in this most general case, we considered mixing through thermal local or global spikes and compound formation. The highly charged Ar[SUP8+]-ion irradiation produced a higher athermal mixing rate compared to singly charged Ar[SUP+] ions, and this result could not be explained by the above models. [ABSTRACT FROM AUTHOR]

Ion beam mixing of Fe/Si bilayers, induced by 100 keV 40Arions at room temperature was investigated. Rutherford backscattering spectroscopy (RBS), atomic force microscopy (AFM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were applied for structural characterization. The main focus of this study was on the influence of the substrate structure on interface mixing. The influence of the substrate structure is due to the two classes of irradiated bilayers, Fe thin films deposited on crystalline or pre-amorphized Si substrates. An about 76% higher efficiency of atomic transport across the pre-amorphized Fe/a-Si interface as compared to that of Fe/c-Si bilayers was observed. [ABSTRACT FROM AUTHOR]

The role of olive oil in human nutrition and its health effects are generally associated with high oleic acid content. Oleic acid as antioxidant reduces risk of cardiovascular and heart disease by reduction of harmful LDL cholesterol. Six samples of olive oil from different producers were used in this work for extraction of oleic acid. Samples used in this study were declared, refined (1 and 2), unrefined extra virgin olive oil (3 and 4) and undeclared unrefined “homemade” oil (5 and 6). The conventional extraction and purification method have been modified and improved in order to make all processes easier and more efficient. Amounts of extracted oleic acid were: 68.24%, (Sample 1), 81.91% (Sample 2), 82.89% (Sample 3), 89.42% (Sample 4), 80.44% (Sample 5), 84.99% (Sample 6). These values were compared with the declared values of the manufacturers on the content of unsaturated fatty acids in their oils. As the amount of oleic acid is the quality indicator of olive oil, for this purpose, peroxide and iodine numbers for each sample were determined. Peroxide numbers in 1g of olive oil for samples 1 to 6 were 10, 11, 14, 14, 13 and 13 nmolO2/kg, respectively. Iodine numbers in 100 g of olive oil in the same samples were: 81, 80, 83, 86, 85 and 84 g I2 respectively. Both peroxide and iodine values are in good correlation with referent values. Structure of all six oleic acid samples after extraction and purification were confirmed by FTIR spectroscopy and boiling point determination. [ABSTRACT FROM AUTHOR]

The role of olive oil in human nutrition and its health effects are generally associated with high oleic acid content. Oleic acid as antioxidant reduces risk of cardiovascular and heart disease by reduction of harmful LDL cholesterol. Six samples of olive oil from different producers were used in this work for extraction of oleic acid. Samples used in this study were declared, refined (1 and 2), unrefined extra virgin olive oil (3 and 4) and undeclared unrefined "homemade" oil (5 and 6). The conventional extraction and purification method have been modified and improved in order to make all processes easier and more efficient. Amounts of extracted oleic acid were: 68.24%, (Sample 1), 81.91% (Sample 2), 82.89% (Sample 3), 89.42% (Sample 4), 80.44% (Sample 5), 84.99% (Sample 6). These values were compared with the declared values of the manufacturers on the content of unsaturated fatty acids in their oils. As the amount of oleic acid is the quality indicator of olive oil, for this purpose, peroxide and iodine numbers for each sample were determined. Peroxide numbers in 1g of olive oil for samples 1 to 6 were 10, 11, 14, 14, 13 and 13 nmolO2/kg, respectively. Iodine numbers in 100 g of olive oil in the same samples were: 81, 80, 83, 86, 85 and 84 g I2 respectively. Both peroxide and iodine values are in good correlation with referent values. Structure of all six oleic acid samples after extraction and purification were confirmed by FTIR spectroscopy and boiling point determination. [ABSTRACT FROM AUTHOR]