Abildtruprosendal7089

The present study reports on the microstructural evolution and room temperature plasticity of V(‑Si)‑B alloys with respect to the V solid solution (VSS)‑V3B2 phase region. To investigate the occurring effects systematically, different binary V‑B and ternary V‑Si‑B alloys were produced by conventional arc melting. Scanning electron microscope (SEM) analyses and X-ray diffraction (XRD) measurements were used to characterize the resulting as-cast microstructures. For the first time, the eutectic composition was systematically traced from the binary V‑B domain to the ternary V‑Si‑B system. The observations discover that the binary eutectic trough (VSS‑V3B2) seems to reach into the ternary system up to an alloy composition of V‑5Si‑9B. Room temperature compression tests were carried out in order to study the impact of single-phase and multi-phase microstructures on the strength and plasticity of binary and ternary alloys. The results indicate that the VSS phase controls the plastic deformability in the VSS‑V3B2 eutectic microstructure whereas the intermetallic V3B2 acts as a strong hardening phase.Prior research has demonstrated that distributed optical fiber sensors (DOFS) based on Rayleigh scattering can be embedded in carbon fiber/epoxy composite structures to rapidly detect temperature changes approaching 1000 °C, such as would be experienced during a high energy laser strike. However, composite structures often experience mechanical strains that are also detected during DOFS interrogation. MEK activity Hence, the combined temperature and strain response in the composite can interfere with rapid detection and measurement of a localized thermal impulse. In this research, initial testing has demonstrated the simultaneous response of the DOFS to both temperature and strain. An embedded DOFS network was designed and used to isolate and measure a localized thermal response of a carbon fiber/epoxy composite to a low energy laser strike under cyclic bending strain. The sensor interrogation scheme uses a simple signal processing technique to enhance the thermal response, while mitigating the strain response due to bending. While our ultimate goal is rapid detection of directed energy on the surface of the composite, the technique could be generalized to structural health monitoring of temperature sensitive components or smart structures.There have been no comparative studies investigating the results of 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) in patients with gastric mesenchymal tumors, including leiomyomas, leiomyosarcomas, schwannomas, and gastrointestinal stromal tumors (GISTs). We retrospectively reviewed the data of 142 patients with pathologically diagnosed gastric mesenchymal tumors treated at 11 institutions. We analyzed the correlation between the maximum standardized uptake value (SUVmax) evaluated using fluorodeoxyglucose-positron emission tomography (FDG-PET) and the tumor size. The correlation between the SUVmax and mitotic index was also investigated in GISTs. The SUVmax (mean ± standard deviation) was 0.5 ± 0.6 in very low-risk GISTs (n = 42), 2.1 ± 0.7 in low-risk GISTs (n = 26), 4.9 ± 0.8 in intermediate-risk GISTs (n = 22), 12.3 ± 0.8 in high-risk GISTs (n = 20), 1.0 ± 1.0 in leiomyomas (n = 15), 6.9 ± 1.2 in schwannomas (n = 10), and 3.5 in a leiomyosarcoma (n = 1). The SUVmax of GISTs with an undetermined risk classification was 4.2 ± 1.3 (n = 8). Linear associations were observed between the SUVmax and tumor size in GISTs, leiomyomas, and schwannomas. The SUVmax of GISTs with a high mitotic index was significantly higher than that of GISTs with a low mitotic index (9.6 ± 7.6 vs. 2.4 ± 4.2). In conclusion, we observed positive correlations between the SUVmax and tumor size in GISTs, leiomyomas, and schwannomas. The SUVmax also positively correlated with the mitotic index and risk grade in GISTs. Schwannomas showed a higher FDG uptake than GISTs and leiomyomas.Compatible surfactant-polymer (SP) hybrid systems at high temperature are in great demand due to the necessity of chemical flooding in high-temperature oil reservoirs. The rheological properties of novel SP systems were studied. The SP system used in this study consists of a commercial polymer and four in-house synthesized polyoxyethylene cationic gemini surfactants with various spacers (mono phenyl and biphenyl ring) and different counterions (bromide and chloride). The impact of surfactant concentration, spacer nature, counterions, and temperature on the rheological features of SP solutions was examined using oscillation and shear measurements. The results were compared with a pure commercial polymer. All surfactants exhibited good thermal stability in seawater with no precipitation. Shear viscosity and storage modulus were measured as a function of shear rate and angular frequency, respectively. The experimental results revealed that the novel SP solution with a mono phenyl and chloride counterions produces a better performance in comparison with the SP solution, which contains mono phenyl and bromide counterions. Moreover, the effect is enhanced when the mono phenyl ring is replaced with a biphenyl ring. Shear viscosity and storage modulus decrease by increasing surfactant concentration at the same temperature, due to the charge screening effect. Storage modulus and complex viscosity reduce by increasing the temperature at a constant angular frequency of 10 rad/s. Among all studied SP systems, a surfactant containing a biphenyl ring in the spacer with chloride as a counterion has the least effect on the shear viscosity of the polymer. This study improves the understanding of tuning the surfactant composition in making SP solutions with better rheological properties.In this study, the phosphonation of a polyaniline (PANI) backbone was achieved in an acid medium by electrochemical methods using aminophenylphosphonic (APPA) monomers. This was done through the electrochemical copolymerization of aniline with either 2- or 4-aminophenylphosphonic acid. Stable, electroactive polymers were obtained after the oxidation of the monomers up to 1.35 V (reversible hydrogen electrode, RHE). X-ray photoelectron spectroscopy (XPS) results revealed that the position of the phosphonic group in the aromatic ring of the monomer affected the amount of phosphorus incorporated into the copolymer. In addition, the redox transitions of the copolymers were examined by in situ Fourier-transform infrared (FTIR) spectroscopy, and it was concluded that their electroactive structures were analogous to those of PANI. From the APPA monomers it was possible to synthesize, in a controlled manner, polymeric materials with significant amounts of phosphorus in their structure through copolymerization with PANI.