Dakshin Kamrup College

The Hydraulic geometry is crucial for understanding the hydrodynamic behavior in fluvial system. The present research analyzes the variation of hydraulic geometry parameters at-a-station and downstream sites along the Kohora River, Assam (India) aiming to quantify the exponential correlation between these parameters and the river’s flow discharge. For this research, six hydrological stations C1,C2,C3,C4,C5 and C6 are utilized to investigate the cross sectional hydraulic properties of Kohora River which are located at various sites along the river course. For each cross-section, a range of hydraulic geometry parameters including width, depth and velocity are recorded at different locations, and subsequent discharge is computed based on these parameters. To complement field-based observations, Landsat 8 satellite imagery (30 m spatial resolution) was processed using ArcGIS 10.7.1 to assess the river basin characteristics. The vegetation characteristics were examined by applying the Normalized Difference Vegetation Index (NDVI), while surface water extent and moisture variability were analyzed through the Normalized Difference Water Index (NDWI), providing supporting insights into catchment conditions influencing fluvial processes. Based on the present study, the mean values of exponents b, f, m which represent the scaling rates of change in width, depth and velocity were determined to be 0.334, 0.538 and 0.134 while the average values of coefficients a, c, k were noted to be 4.46, 0.56, 0.40 for at-a-station hydraulic geometry. For downstream hydraulic geometry, the exponents b, f, and m were 0.2, 0.4, and 0.4, while the coefficients a, c, and k were 5.19, 0.57, and 0.35. These values indicate a positive exponential relationship between the downstream hydraulic geometry parameters and flow discharge in Kohora River. The outcome of the present study is expected to be applicable to improving the watershed management of the river basin.

We have conducted detailed high-resolution spectroscopic studies on three extremely metal-poor (EMP) stars HE 0401-0138, HE 1153-0518 and HE 1246-1344. For the stars HE 0401-0138 and HE 1246-1344, we have estimated the abundances of C, Na, Mg, Ca, Sc, Ti, Cr, Mn, Co, Ni, Sr and Ba along with the upper limits for Li, O, La, Ce, Pr, Nd, Sm, and Eu. For HE 1153-0518, abundances of seven light elements from C through Ni and two heavy elements, Y and Ba, have been derived, together with upper limits for Li, O, and La. Based on their observed abundance patterns, HE 0401-0138 and HE 1246-1344 are classified as normal EMP stars, whereas HE 1153-0518 is identified as a newly discovered CEMP-no star. HE 1153-0518 shows strong carbon enhancement with a high absolute carbon abundance, extreme sodium enrichment, very low neutron-capture element abundances, and a very low carbon isotopic ratio (12C/13C = 2.0). Its spectral energy distribution shows clear infrared excess, indicating the presence of circumstellar dust. The abundance pattern of HE 1153-0518 suggests enrichment by early nucleosynthetic processes, such as faint core-collapse supernovae with mixing and fallback, while the possibility of binary interaction and subsequent internal mixing cannot be ruled out. The discovery and detailed study of HE 1153-0518 add an important object to the small population of high-A(C) CEMP-no stars and provide valuable constraints on early chemical enrichment pathways and the nature of the first generations of stars.

The growing demand for wearable electronics necessitates energy‐storage solutions that offer good electrochemical performance and flexibility. In this context, graphitic carbon nitride (g‐C 3 N 4 ) and polypyrrole stand out as promising candidates due to their electric double‐layer capacitance and redox‐active behavior, respectively. However, achieving optimal specific capacitance while integrating both components onto a flexible substrate is challenging. This article addresses the issue by optimizing the concentration of polypyrrole nanoparticles (PPy NPs) within g‐C 3 N 4 nanosheets to enhance specific capacitance. In‐situ chemical oxidation is employed to grow PPy NPs within g‐C 3 N 4 nanosheets at varying concentrations. The obtained nanocomposites are drop‐cast onto carbon cloth, and their electrochemical performance is investigated systematically. The nanocomposite synthesized with 0.1 M pyrrole concentration within 0.1 mg ml −1 of g‐C 3 N 4 (GP‐2) shows optimal specific capacitance of 568 F g −1 at a current density of 1 A g −1 . This is further corroborated by an enhanced surface area and pore density, as determined from Brunauer–Emmett–Teller analysis along with minimum charge‐transfer resistance (25 mΩ) in the impedance spectra. This study, therefore, suggests that the developed g‐C 3 N 4 /PPy NPs nanocomposite exhibits the potential as a promising electrode material for flexible energy‐storage applications.

Groundwater is indeed vital for ecosystems and socio-economic stability. It supports the growth of plants and provides habitats for various organisms, contributing to ecological balance. Additionally, it serves as a reliable source of drinking water for communities and fuels agricultural activities, thereby enhancing socio-economic stability within nations. Presently, the rapid extension of anthropogenic activities including urbanization, industrialization and agricultural modernization has been continuously deteriorating the physicochemical qualities of underground water resulting adverse effect on human health and environment respectively. The industrial wastes are the principal factors for the degradation of groundwater quality as this act like a source of heavy metal pollutant. This research focused on the assessment of Heavy metal contents in groundwater and its impact on human health and surrounding environment of industrial areas in South Kamrup Region of Assam, India. To achieve this goal, samples of groundwater are collected from various industrial sites of Palasbari,Bijoynagar, Mirza, Loharghat, Rani and Dharapur area of south Kamrup in pre monsoon season, January, 2024 and are analyzed for physiochemical properties such as pH, TDS ( Total dissolve Solids) and major Heavy metal contents (As, Cd, Pb, Mn,)in laboratory by applying FL/SOP/ICPMS-01 method based on APHA 23rd Ed.2017 at FARE LABS private Limited, M.G road, Gurugram. Result shows that heavy metals concentration in all groundwater samples is fall under the current drinking water standard given by WHO, 2022. Findings show that the maximum HPI (Heavy Metal Pollution Index) value is estimated from the ground water sample of Mirza is greater than 90 (>90). Thus, it is perceived that the ground water of Mirza is moderately contaminated while remaining sampling sites fall under low heavy metal contamination category (HPI, < 90). In addition to this, maximum TDS value and pH value were detected from Palasbari is 230 ppm and Mirza that is 8.1 respectively. Consequently, in order to show the heavy metal contents, TDS and pH values, groundwater maps are prepared using ArcGIS software.