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The effect of Ta and Nb (25 at %) on the thermal, mechanical, and corrosion behaviors of TiNi shape memory alloy has been investigated. Ta and Nb added TiNi shape memory alloy samples that were prepared using the arc melting technique. The composition and crystal structure of the TiNi alloys were characterized by SEM-EDX and XRD at room temperature. The Vickers microhardness technique was used for the microhardness of the samples. Differential Scanning Calorimetry (DSC) was used to determine the thermal behavior of the TiNi shape memory alloys. DSC results showed that after four different heating-cooling rate, both austenite transformation temperatures and hysteresis temperature were increased in both Ti50Ni25Nb25 and Ti50Ni25Ta25 alloys. The enthalpy and entropy change with elastic energy, and Gibbs free energy were calculated of Ti50Ni25Nb25 and Ti50Ni25Ta25 SMAs. The phases of the alloys were determined using the XRD pattern. SEM and OM results show that both alloys solidified in dendritic structure. Corrosion biocompatibility of the new alloy samples were studied by potentiodynamic corrosion technique in simulated body fluid. The corrosion test indicated that Nb has a more positive effect than Ta on the corrosion of the new SMA alloys, suggesting TiNiNb SMA to be better biocompatibility than TiNiTa SMA. [ABSTRACT FROM AUTHOR]

It is aimed to investigate the coating of AISI316 stainless steel with NiCrBSi/WC at different ratios using TIG method. In this study, the Ni-based WC-reinforced MMC layer was manufactured by the TIG composite coating method, and then the microstructure of the coating layer was examined. Microstructure and phase components of the composite coatings were characterized by optical microscopy, scanning electron microscopy, and X-ray diffraction. A metallurgic bound was found between the coating layer and the substrate through the TIG coating process. WC was re-solidified in the matrix by dissolving with high input energy. Several phases were found, including Ni-rich (γ -Ni) primary dendritic phase, Ni-Ni3B, and Ni3Si eutectic structure, Cr7C3, Cr2B3, Cr3Ni2, Ni2W4C, and Ni 1 7 W3 phases in dendritic structures. The presence of carbides in the structure had affected the hardness of the coating. The maximum hardness value was found to be 469.5 HV and the hardness of the coating layers was increased at least 2.5 times compared to that of the substrate material. [ABSTRACT FROM AUTHOR]

The physicochemical properties of tarhana soup produced with different dough treatments, fermentation times, and preservation methods were examined. Tarhana doughs were prepared with yogurt (control) or baker's yeast (Saccharomyces cerevisiae) and fermented for 3 days. Samples were taken at 24, 48, and 72 hr. Samples were then preserved via one of four methods: sun dried, dried in the shade, vacumn dried, and frozen. Frozen samples produced lower organic acid levels after 72 hr of fermentation in both control (0.68 g/100 g) and yeast (0.61 g/100 g) applications than samples that were dried (0.94 g/100 g control samples; 0.81 g/100 g samples with yeast). Increasing fermentation time resulted in a significant effect on the formation of organic acid in the tarhana (p < .01). At 72 hr of fermentation, total acidity increased 11%, 17%, and 23% for tarhana samples vacumn-dried, sun-dried, and dried in the shade, respectively. Preservation methods also affected the moisture, ash, crude protein, total acidity, pH, salt, fat, reducing sugar levels, and the sensory assestment of tarhana soup (p < .01). Sensory characteristics were not significantly affected by baker's yeast in any of the preservation methods used (p > .01). However, sensory scores for tarhana prepared from the samples dried in a sheltered area showed a reduction in color desireablilty as the fermentation time increased. The soup prepared from frozen tarhana (72 hr fermentation, with yeast) had the highest scores with respect to color, mouth feel, flavor, and overall acceptability. Vacuum-dried samples' scores in these areas were also high in comparison to the two other drying methods.

The effects of a single topical dose of angiotensin II (AII) on prelamination of flaps were investigated in rats using an immunohistochemical marker. Ninety rats were randomly divided into three groups (n = 30 in each). The control group were given nothing; the vehicle group were given only carboxymethyl cellulose, and the treatment group were given topical AII with carboxymethyl cellulose between the flap and the skin graft. According to the day of evaluation of vascularisation, each group was randomly divided into three sub-groups on days 4, 7, and 14 (n = 10 in each). Paraffin sections of the tissues were cut at the flap-graft interface and stained immunohistochemically with factor VIII-related antigen (FVIIIRAg). Capillaries and venules that stained were counted. The number of vessels in the groups on day 4 were similar, but by day 7 the number of vessels was significantly greater in the treatment group than the other two. The number of vessels in the treatment group on day 14 was greater than in the other two groups, but not significantly so. We conclude that a single topical dose of AII increases the vascularisation at the flap and skin graft interface by angiogenesis.