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Investigating Bidirectional Flows in a Quiescent Prominence Using MAST Ca II 8542 Å Line Scan Observations
No full textQuiescent prominences are large magnetic structures hosting cool plasma in surrounding million-degree solar coronae. Prominences host different flows that may distort magnetic field lines, which may lead to magnetic reconnection inside the prominence body. In this study, we investigate bidirectional flow patches in a quiescent prominence. The investigation included the analysis of velocities in the line of sight (LOS) and the plane of sky (POS) of the prominence, complemented with intensity at different spectral positions of the Ca II 8542 Å line. The LOS velocities were obtained using Gaussian fitting to the observed Ca II spectra, whereas the POS velocities were derived from a position−time diagram along a vertical slit in the region of interest (ROI). Complementary to Ca II 8542 Å line scans, EUV intensity images from the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory were analyzed to investigate the multithermal nature of the observed bidirectional flows. Out of two ROIs, in the first ROI, a large central patch of bidirectional flow was present initially that merged with other patches and disappeared approximately 30 minutes from the beginning, followed by the generation of another set of patches. Cospatial with diverging LOS motions of order 10 km s−1 associated with patch dynamics, POS motions of similar order were also observed in the ROI. Diverging intensity enhancements in different AIA channels, indicating a multithermal nature of bidirectional flows, were observed cospatially with diverging flows in the POS. Similar dynamics were observed in the second ROI. Bidirectional flow patches and the associated dynamics in LOS and POS may be related to magnetic reconnection inside the prominence
Highly efficient mutual separation of Nd-Pr by the selective dissolution of Nd into an ionic liquid containing1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedione
No full textThe separation of Nd from Pr in the mixture is one of the challenging tasks. The present investigation exhibited the unprecedented mutual separation of Nd and Pr from the physical mixture of Nd2O3 and Pr6O11 by selective dissolution of Nd into an ionic liquid, 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide) ([C4mim]NTf2) phase containing 1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedione (HFOD) for stabilizing Nd3+ by enolate ion complexing in the ionic liquid phase. The water content of ionic liquid, the concentration of HFOD, and the frequency of stirring improved the extent of dissolution. However, Pr dissolution in measurable quantity showed detrimental effect in their mutual separation. The sintering of the precursors led to agglomeration of the particles obtaining bigger in size with low defect fraction thereby resulting in the reduction in the extent of dissolution due to the availability of lower surface area. The relative composition of Nd2O3 and Pr6O11 influenced the mutual separation as also observed for the total amount of solid required to be process with respect to the unit ionic liquid phase volume. The dissolution being exothermic, the extent of dissolution reduced at higher temperature thereby registering an impact on the mutual separation. The nature of the ionic liquid also influenced the dissolution characteristics with a trend in the mutual separation as [C4mim]NTf2 6mim]NTf2 8mim]NTf2
Synergism in enzyme-nanomaterial constructs for select applications in environment and food
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Impacts of drought on surface water storage in India
No full textWater bodies such as lakes and reservoirs are essential components of the hydrological cycle, providing water for agriculture, domestic use, industry, and supporting biodiversity and energy production. In India, especially in arid and semi-arid regions, these water bodies serve as vital lifelines by storing monsoon precipitation and ensuring year-round water availability. Despite their importance, the large-scale impact of drought on Indian water bodies has not been thoroughly explored. This study examines spatio-temporal variations in water area and quantifies the impacts of drought using remotely sensed data from Landsat satellites (4, 5, 7, and 8) and climate variables from 1990 to 2018. The results indicate that 35% of water bodies show significant declining trends, with average reductions of 10% in the long-term mean maximum area and 5% in the minimum area. The decline in water area is most pronounced during droughts, severely affecting small water bodies that shrink more rapidly than medium and large ones. Moreover, the duration of a 20% reduction in water area decreases by 1 month during drought periods. The findings reveal that combined monsoon and post-monsoon droughts have significantly impacted water areas, particularly in central and southern India. Therefore, the rapidly shrinking water bodies identified in this study can contribute to improved water resource management by enabling the development of an early warning system in India
Advancing CCS in India: Policy Developments, Funding Mechanisms, and the Potential of Basalt Storage Solutions
No full textCarbon Capture and Storage (CCS) is crucial for reducing emissions in hard-to-decarbonize sectors such as cement, steel, and power generation. For India, heavily reliant on coal, CCS provides a means to lower emissions while maintaining energy security. While global CCS deployment has gained momentum through policy support and funding, high costs remain a significant challenge. In India, basalt formations, especially in the Deccan Traps, present a promising and cost-effective option for CO2 storage through mineralization. India's CCS policy is still in development, with short-term incentives like carbon credits and potential long-term goals, such as carbon taxes, being considered. To scale CCS, India requires robust funding mechanisms, technological innovation, and large-scale CCS clusters. International collaboration and investment will be essential in addressing financial and technological barriers. With the right infrastructure, research, and policy framework, CCS can become a key component of India's strategy to meet its net-zero target by 2070
Particle number diffusion in second-order relativistic dissipative hydrodynamics with momentum-dependent relaxation time
No full textThis article explores particle number diffusion in relativistic hydrodynamics using kinetic theory with a modified collision kernel that incorporates the momentum dependence of the particle relaxation time. Starting from the Boltzmann equation within the extended relaxation time approximation (ERTA), we derive second-order evolution equations for the dissipative number current and calculate the associated transport coefficients. The sensitivity of transport coefficients to the particle momentum dependence of the collision timescale of the microscopic interactions in the hot QCD medium is analyzed. For a conformal, number-conserving system, we compare the ERTA-modified transport coefficients for particle diffusion with exact results derived from scalar field theory. With an appropriate parametrization of the relaxation time, we demonstrate the consistency of our analysis and assess the degree of agreement of the results with the exact solutions from scalar field theory. The relaxation times for the shear and number diffusion evolution equations are seen to be distinct in general when the momentum dependence of the relaxation time is taken into consideration
