Concentration-dependent luminescence characterization of terbium-doped strontium aluminate nanophosphors.

The present investigation describes the synthesis of luminescent terbium-doped strontium aluminate nanoparticles emitting bright green light, which were synthesized through a solid-state reaction method assisted by microwave radiation. Various samples containing different concentrations of Tb were synthesized, and an analysis of their structural and morphological features was conducted using powder x-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The band gaps of the samples were determined utilizing the Kubelka-Munk method. The quenching mechanism observed was identified to be due to dipole-dipole interaction using the Dexter theory. The optimized sample with a terbium concentration of 4 at.% has a luminescence lifetime of 1.05 ms with 20.62% quantum efficiency. The results of this study indicate that the terbium-doped strontium aluminate fluorescent nanoparticles exhibit promising potential for a wide range of applications, including bioimaging, sensing and solid-state lighting.

Synthesis and Characterisation of SrAl2O4: Eu3+ Orange-Red Emitting Nanoparticles.

The current study involves the synthesis and characterisation of europium doped strontium aluminate nanophosphors using the solid-state reaction method with varying concentrations of europium. The existence of the SrAl2O4 phase in all samples was verified using X-ray diffraction and FTIR analysis. The lattice parameters as well as phase fractions were determined using Rietveld refinement. Surface morphology was studied using field emission scanning electron microscope. Using the Tauc plot method acquired from the diffuse reflectance spectra, the band gaps of the samples were determined and it was found that the doped samples possess lower band gaps compared to the host. Our findings demonstrate that these nanophosphors exhibiting bright orange-red emission under UV excitation with quantum efficiency 70.68%, can be applied for display and fluorescence imaging.

What is in a Meter? A Qualitative Exploration into the Implementation of Electricity Metering Across Mumbai Communities Using Normalisation Process Theory.

Metering is fundamental in the efficient operation of electricity networks, as meters facilitate controlled usage and improve health and well-being. However, across the Global South, meters have often been found to be lacking or not fit for purpose. Therefore, this study sought to determine residents' perceptions and access to electricity metering across a community in Mumbai, with the goal of developing recommendations to support the implementation of meters in the future. Fifty semi-structured interviews were conducted by phone, with participants from different areas and socioeconomic classes, within Greater Mumbai. The sample consisted of 20 low-income, 20 middle-income, and 10 high-income participants. The Normalisation Process Theory (NPT) was used to inform the interview schedule and to organise the thematic analysis. Meter accessibility and location was variable across the participant groups, as was the education and awareness of metering technology. Socio-political factors were found to directly affect the use of meters, specifically in the low-income group. The high cost associated with metering was a prominent finding; with a preconception that introducing meters would only increase utility expenditure. Future work should focus around ensuring meters are easy to use, practical and accessible to all residents and supporting education programmes around how to use a meter and how they can reduce utility expenditure. The cost of meters should also be investigated, to establish that the costs, associated with introducing new meters, are not passed disproportionately to consumers. Supplementary Information: The online version contains supplementary material available at 10.1007/s43477-022-00059-y.

Physical distancing on public transport in Mumbai, India: Policy and planning implications for unlock and post-pandemic period.

COVID-19 outbreak affected the daily lives of people around the globe, and authorities proposed numerous interventions to make activity participation and traveling safer during the pandemic period. This study investigates the potential implication of such interventions on executing physical distancing on public transport in Mumbai, India. The study reviews the demand-supply gap of public transport during the pre-pandemic and pandemic period and evaluates the challenges in practicing physical distancing with the short-term interventions, such as lockdown guidelines at different phases and long-term interventions, such as flexible work arrangements, on public transport. The study findings indicate that physical distancing on public transport is difficult to achieve at peak hours, even with the very high travel restrictions and lockdown measures, unless flexible work arrangements are implemented. The flexible work arrangements, such as staggered working hours and work from home, can significantly reduce peak-hour demand and total excess demand without altering the supply pattern. The study can guide in constituting transport and broader policy decisions, including developing low-risk public transport for the post-pandemic period.