The Great Mica Belt of Jharkhand, India, is an intensively disturbed mining region due to long-term mica extraction, which increases anthropogenic pressures on environmental components. Despite the environmental fragility of this region, systematic baseline information on rainwater chemistry and trace metal deposition has been lacking, particularly in comparison to other mining-impacted regions where such studies are more extensively documented. Addressing this gap is crucial for understanding atmospheric deposition processes in mining-dominated landscapes of eastern India. Unlike previous studies that predominantly focus on coal-mining, urban, or industrial regions, this study specifically investigates a mica-mining dominated environment, which has distinct mineralogical composition and emission characteristics influencing rainwater chemistry. This study aims to evaluate the chemical composition and trace metal concentrations of monsoonal rainwater collected at Koderma and Tisri within the Great Mica Belt. A total of 60 rain water samples were analyzed for physicochemical parameters (pH, EC, TDS), major and minor ions (i.e., Ca2⁺, Mg2⁺, Na⁺, K⁺, Cl⁻, HCO₃⁻, SO₄2⁻, NO₃⁻, NH₄⁺ and F⁻), and metals. Source contributions were evaluated using enrichment factor (EF), non-sea-salt fraction (nssf), and neutralization factor analyses. Rainwater pH ranged from 5.38 to 7.26, indicating acidic to alkaline conditions, with 9
In this work, the structural, electrical, electro-thermal, and switching properties of As2Se3-doped Ge2Sb2Te5 films have been studied. Upon annealing, the films undergo a phase transition at higher temperatures from the amorphous state to a stable hexagonal phase via a metastable face-centered-cubic phase, notably without any observed phase separation and lattice distortion. Doping with As2Se3 significantly improves the thermal stability of the amorphous phase, increasing the crystallization temperature from-168 degrees C to-225 degrees C (x = 0.21). The band gap is increased due to the formation of high-energetic Ge-Se and As-Se bonds. Furthermore, the data retention temperature for a 10-year period is substantially improved from 78 degrees C to 124.93 degrees C with a corresponding increase in the activation energy. The threshold current required for phase transformation is reduced to 0.23 mA. Higher-doped films generate more Joule heat due to their increased resistivity, which, in turn, allows for a reduction in power consumption for the same applied current, indicating promising applications in phase change memory devices.
The dynamics of sub-barrier fusion reactions are well explained by incorporating channel coupling effects to various degrees of freedom, such as deformations and vibrations, within the coupled channel formalism. In many systems, sub-barrier fusion cross-sections are enhanced by couplings to inelastic excited states and nucleon transfer channels with positive Q-values. However, several systems show no such effect from positive Q-value transfer channels. Conventional coupled channel approaches effectively handle even-even systems, but for odd-even systems, odd-A nuclei are often approximated as pure rotors or vibrators, assuming ground state spin-parity and neglecting spin reorientation effects. Furthermore, single nucleon transfer is not included in codes like CCFULL, which only account for ground-state pair transfers without considering transfers involving excited states. To address these limitations, the quantum mechanical coupled reaction channel (CRC) code FRESCO is employed. For the 19F + 68Zn system, experimental data are explained by including couplings to inelastic states of both projectile and target. However, for 19F + 54,56Fe, 64Zn and 142,150Nd systems, inelastic couplings alone fail to reproduce fusion excitation functions (EFs). Couplings to one-proton (pickup) or triton (stripping) transfer channels with positive Q-values show no significant effect on sub-barrier fusion cross-sections. Overall, CRC calculations indicate that coupling to inelastic states of both projectile and target enhance sub-barrier fusion cross-sections. The treatment of the projectile/target nuclei based on certain assumptions has resulted in different sub-barrier fusion cross-sections in earlier studies. The current study suggests that channel coupling effects on fusion excitation function is a complex process in interaction with odd-A projectile and one needs to include exact spin-parity of odd-A nuclei in theoretical calculations.
In the pursuit of advanced space technologies, wide and ultrawide bandgap semiconductors are benchmarked by their ability to withstand high radiation environments. This work examines the detailed material and device characteristics of β- Ga 2 O 3 -based Schottky barrier diodes (SBDs) exposed to high-intensity 60 Co γ -ray irradiation, with cumulative doses up to 200 kGy. The SBDs exhibit remarkable performance and stability for different diode sizes over the high γ -ray doses, maintaining ideality factor (IF) close to unity and Schottky barrier height (SBH) around 1.10 eV. The IF increases to 1.11 from 1.03 when it is irradiated with 200 kGy, while the SBH decreases from 1.10 eV to 1.07 eV. Comprehensive material characterizations on the halide vapor phase epitaxy-grown pristine as well as irradiated β- Ga 2 O 3 epilayers reveal the dose-dependent variations in surface morphology, lattice strain, and optical absorption. Importantly, the small values of carrier removal rates (0.03 cm −1 ), even upon such high doses, establish the resilience of β -Ga 2 O 3 –Pt–Au diodes towards the extreme conditions. This detailed study on the γ -ray tolerance of the β- Ga 2 O 3 material, combined with its device performance up to 200 kGy, reinforces its potential for next-generation space exploration technologies.
This study from Hulas Khera, in the Central Ganga Plain, reconstructs past climatic conditions and lake-level fluctuations since similar to 6350 calibrated years BP. It integrates sediment textural analysis, mineral magnetism, elemental composition, and AMS radiocarbon dating. Variations in detrital input reflect catchment erosion associated with shifts in rainfall patterns, indicating precipitation as the primary driver of magnetic property changes. The C-M diagram indicates floodplain deposition, driven by suspension settling. Grain-size end-members EM1 and EM2 (mean sizes: 8.9 and 53 mu m) in the fine to coarse silt domain are associated with surface runoff during periods of heightened seasonal precipitation, corresponding to intensified Indian Summer Monsoon activity around 5400 to 4600, 4000, 3300, 2000, and 800 cal yrs. BP. In contrast, EM3 and EM4 (mean sizes: 92 and 160 mu m), within fine sand domain, are prominent during intervals of extended drought and monsoon minima around similar to 6300-5400, similar to 4300, similar to 3600, similar to 2800-2200, similar to 1800-900, and similar to 600-300 cal yrs. BP, coinciding with regional dry phases recorded in the Kanwar Lake record from the Central Ganga Plain, and reduced upwelling record of the Arabian Sea. Abrupt shifts in Indian Summer Monsoon (ISM) strength recorded correspond to known monsoon minima during the Little Ice Age and the Dark Age Cold Period, highlighting the sensitivity of regional hydrodynamics to mid- to late-Holocene monsoonal variability.
