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Hybrid nanomaterials with distinct properties and morphologies when clubbed within a sensor matrix can generate a synergistic effect on molecular sensing. In this work, creation of such nanohybrid platform has been attempted for rapid detection of hydrogen peroxide (H2O2), which has tremendous role in area of medical diagnostics. Conventionally, the peroxidase (POD) enzyme catalyzes H2O2; however, it is prone to inherent chemical and thermal instabilities reducing the overall stability and shelf life of sensor probe. A possible solution for this problem has been attempted in this work where a nonenzymatic peroxidase mimic nanohybrid probe comprising gold nanodendrites (AuND), nickel metal organic framework (Ni-MOF), and hydrazine has been synergistically deployed for rapid detection of H2O2. The developed sensor probe has been rigorously characterized through various characterization techniques, including scanning probe microscopy (SPM), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX-mapping), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The probe demonstrated impressive analytical performance, possessing a linear dynamic range (LDR) between 1 × 10–8 M and 1 × 10–15 M and a limit of detection (LOD) of 0.34 (±0.05) × 10–15 M. The probe's average response time with changing H2O2 concentrations was 5.02 ± 0.42 s, making it an agile sensing platform for H2O2 detection. The nanohybrid probe displayed minimal response toward interferants such as superoxide radicals, ascorbic acid, cysteine, glucose, alanine, and citric acid, which usually coexist in a real sample matrix. In order to investigate the real-life applicability of the developed sensor probe, a real sample analysis involving synthetic serum was adopted, which yielded a current recovery between 90.20 and 94.14%. The probe fabrication time and on-chip synthesis procedure are facile, making it a robust and efficient sensing platform for H2O2 free radicals in clinical settings. [ABSTRACT FROM AUTHOR]

In the cardiovascular diseased (CVD) conditions, it is essential to choose a suitable rheological model for capturing the correct physics behind the hemodynamic in the multiply afflicted diseased arterial network. This study investigates the effect of blood rheology on hemodynamics in a blood vessel with abdominal aortic aneurysm (AAA) and right internal iliac stenosis (RIIAS). A model with AAA and RIIAS is reconstructed from a human subject's computed tomography (CT) data. Localized mesh generation and pulsatile inflow condition are considered. Non-Newtonian models such as the Power-law, Carreau, Cross, and Herschel Berkley models are used in simulations. The outcome from a validated computational model is compared with the Newtonian model to identify the suitable model for dealing with pathological complications under consideration. The capabilities and significance of various rheological models are also examined via Wall Pressure (WP), Wall Shear Stress (WSS), velocity, Global non-Newtonian importance factor (IG), Vorticity Streamlines, and Swirling Strength. It is noted that during the entire cardiac cycle, the IG factor of the cross model is found to be relatively more significant. Power Law depicts larger IG factor during peak systole and early diastole. Also, the cross model depicts larger WSS, WPS, swirling strength distribution and vorticity during the peak systolic and diastolic phases It is noted that IG ∼0.02 is an appropriate non-Newtonian blood activity cut-off value in the descending abdominal artery having AAA and RIIAS. The critical important WSS values are in the range of 0–9 Pa which is stated in WSS contour plot. [ABSTRACT FROM AUTHOR]

Flyash, a waste product generated in large quantities in thermal power plants, has been posing problems of disposal. The purpose of the present work was to make a meaningful utilization of flyash as filler in neat epoxy resin matrix and 2% Polybutyleneterepthalate (PBT)/epoxy blend matrix. For this purpose, the tensile, flexural, compression, impact, chemical resistance, and water absorption properties were studied. Composites were made with varying proportion of flyash in epoxy resin and 2% PBT/epoxy blend matrix. Tensile, flexural, and compression properties were measured on a computerized universal testing machine, according to ASTM procedures. Impact strength was determined using izod impact tester for un-notched specimens. PBT (2%)/epoxy blend matrix composites showed improved mechanical properties over neat epoxy flyash composites. All the composites were found to have good chemical resistance toward acids, solvents, and alkalies. These composites showed better water resistance over neat epoxy flyash composites. POLYM. ENG. SCI., 46:946-953, 2006. © 2006 Society of Plastics Engineers, INTRODUCTION Epoxy resins are considered to be the most important class of thermosetting polymers and are extensively used in coatings, adhesives, and in several other engineering applications. Once these epoxy [...]