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Manned space programme has become inevitable in the modern world. One important aspect in such endeavors is getting the crew back to home safe and sound. Re-entry capsules are widely used for bringing back astronauts back to the Earth. The re-entry mission is a very crucial one, with speeds up to 30 times than that of sound and temperatures hot enough to ionize air. The study and design of a re-entry capsule has to be done with utmost concern over the life of returning astronauts. In this paper, simulations carried out over a re-entry vehicle for various free-stream conditions such as subsonic, supersonic and hypersonic flow regimes. Results were obtained by solving compressible Navier-Stokes equation with k-omega turbulent model. Simulations were carried out for various inlet conditions corresponding to an altitude of a re-entry vehicle by using CFD code SU2. The geometrical parameters of a re-entry vehicle such as spherical nose radius and cone angle were varied and the effects of the aerodynamic phenomena such as shock wave, flow separation and wake formation over a downstream of a module were studied. In this paper, the results pertaining to the pressure distribution, the Mach contour and temperature over a module is presented.

This paper is a bibliometric overview and evaluation of peer-reviewed articles on governance in higher education. The study uses meta-data from the Scopus journal repository, retrieved using relevant keywords. We analyse the data in VOSviewer software. A content analysis of selected papers is undertaken to comprehend the thematic focus of the knowledge domain. Results show that the field of this research topic has grown exponentially both qualitatively and quantitatively. The conceptual dynamics of the literature unfold the multidimensionality of the topic of this inquiry. Our significant contributions are the scholarly audit of higher education governance research and the identification of several structured research questions for future investigations. This is a maiden attempt to employ bibliometric and content analysis for science mapping and qualitative review in the topic of inquiry.

This study explores the comprehensive characterization of Y3+ and Co2+ co-substituted LaFeO3 nanoparticles synthesized via the sol-gel auto-combustion method. The synthesized samples, La1-xYxFe1-y CoyO3 (x = 0,0.10 and y = 0,0.03,0.05,0.07) were characterized by employing various techniques such as x-ray diffraction (XRD), Scanning Electron Microscopy (SEM) with EDX, Raman spectroscopy, UV-visible spectroscopy, and Vibrating Sample Magnetometry (VSM). The Raman and XRD analysis, supported by Rietveld refinement, provided conclusive evidence of a pure orthorhombic LaFeO3 phase. Microstructural studies unveiled an agglomerate-type, irregular particle distribution, while EDX analysis confirmed the elemental composition. The XPS study gives evidence about the presence of both Fe2+ and Fe3+ oxidation states, and Co has a Co3+ oxidation state. UV-vis spectroscopy demonstrated enhanced visible light absorption, revealing a reduced bandgap with increasing doping percentages. VSM measurements exhibited M-H loops, substantiating the weak ferromagnetic nature of the materials. Moreover, these nanoparticles exhibit dielectric constants and low dielectric losses, making them suitable for use in devices for communication. Overall, these findings may offer valuable contributions to the understanding of nanomaterial characteristics for potential applications in diverse fields. Research Highlights: Synthesis of La1-xYxFe1-y CoyO3 (x = 0,0.10 & y = 0,0.03,0.05,0.07) nanoparticles by sol-gel method. Confirmation of orthorhombic structure with Pbnm space group from XRD, Rietveld and Raman analysis with a decrease in crystallite size from 48 to 12 nm. Disclosement of the presence of both Fe2+ and Fe3+ oxidation states and Co doping has a Co2+ oxidation state from XPS analysis. The bandgap tuning from 2.09 to 1.56 eV with an increase in Co2+ doping concentrations. Weak ferromagnetic behavior observed for all the NPs. Enhanced Ms, Mr, and Hc for the 7% Co2+ doped LFO. The 7% Co2+ doped LFO exhibited the highest dielectric constant, lowest tangent loss and highest conductivity. [ABSTRACT FROM AUTHOR]