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Excellent power density, quick charge/discharge rates, and great energy storage capacity of lead-free dielectric ceramic capacitors have drawn a lot of interest. In this work, doping with Bi_0.88La_0.12ScO₃ (BLS) enhanced the relaxation behavior and energy storage characteristics of Bi_0.5Na_0.46Li_0.04TiO₃ (BNLT)-based ceramics. Grain size was greatly lowered from 3.4 to 1.79 μm and XRD and SEM studies revealed that the doped La³⁺ and Sc³⁺ ions were effectively integrated into the matrix lattice. The relaxable index of the ceramics reached 1.92 as the BLS doping content rose; likewise, the recovered energy density (W_rec) and energy efficiency (η) improved. Excellent energy storage properties (W_rec = 5.62 J/cm³, η = 81%) were shown by the BNLT-0.09BLS ceramic under a field strength of 350 kV/cm. In the temperature range of 30 to 200 °C and frequency range of 5 to 150 Hz, it also displayed good frequency stability and thermal stability. Moreover, charge/discharge experiments showed that the ceramic has an ultra-fast discharge rate (t_0.9 = 0.18 μs). These outstanding comprehensive characteristics of BNLT-0.09BLS ceramics provide a valuable source of reference for the design of effective dielectric capacitors.

Urban stormwater runoff could be a significant non-point source of surface water pollution during India’s monsoon season (June – September). This study aims to characterize the stormwater runoff in the Powai region of Mumbai and investigate interlinkages between precipitation characteristics and runoff quality. The levels of conventional water quality parameters (physical, chemical, microbiological) and emerging contaminants in the runoff were determined. Runoff samples were collected from various outfall locations (SL1, SL2, SL3, SL4 and SL5) which drain into the Powai Lake. Runoff sampling was conducted for ten storm events spread over the 2022 and 2023 monsoon seasons. Two outfall locations (SL4, SL5) convey runoff originating primarily from an institutional township, and have reported the lowest organic loads and fecal contamination. However, runoff within the township contains elevated levels of metals such as iron, lead and Aluminum. In addition, emerging contaminants such as phthalates, pesticides, pharmaceuticals and personal care products were detected in the runoff. The runoff outside the township (SL1, SL2, SL3) had low DO levels and highest mean concentrations of TSS, BOD, and oil and grease. The potential mixture of untreated sewage with runoff was identified as the probable cause for low DO, which was further substantiated by the high fecal coliform loads (1600 MPN/100 mL). The findings from this study identify runoff as one of the dominant causes of degrading water quality and will serve as a reference to further scientific efforts in quantifying the pollutant loads, and development of export coefficients for the Powai Lake watershed.

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In this investigation, we study the dynamics of a diffusive prey-predator system in a time-periodic environment, incorporating prey refuge and supplementary food resources for predators. We establish solution’s boundedness, and derive the conditions for population persistence and extinction. We find that whenever both prey and predator populations persist, a unique periodic solution arises that is globally asymptotically stable. Our numerical results show that increasing prey refuge (or alternative food) stabilizes the system, shifting it from oscillatory behavior to stable coexistence. However, excessive alternative food availability can drive prey species to extinction, leaving predator as the sole surviving species. Further, we observe that a time-periodic environment significantly affects oscillatory patterns, driving transitions between uniform bulk oscillations and oscillating Turing patterns. Overall, our study highlights the crucial influence of time-periodic environmental factors on prey-predator dynamics, considering prey refuge and additional food for predators, and stresses the need to account for such variability in ecological systems.

Biological silk is a natural optical waveguide with humidity-sensitive properties. The refractive index (RI) is a critical parameter that determines the optical properties of waveguides and is greatly affected by humidity. In this article, we propose an optical method for real-time measuring the RI of micron-scale biological silks at different humidity. We employ a section of single-mode fiber (SMF) and a section of biological silk to configure an F-P cavity structure. By recording the spectrum and diameter of the silk under different humidity, we can obtain the relationship among free spectral range (FSR)、diameter, and relative humidity (RH). Based on this relationship, we calculate the variation of RI with humidity. We measure three materials in the 30–80% RH range. The measurement results indicate that during this process, the RI of spider egg sac silk (SESS) ranges from 1.491 ± 0.003 to 1.412 ± 0.009, mulberry silk is 1.551 ± 0.009 to 1.473 ± 0.005, and radial silk is 1.549 ± 0.005 to 1.479 ± 0.003. The relative uncertainty in the range ± 5 × 10^− 3 to ± 7 × 10^− 3 is achieved for these challenging samples. This rapid and convenient measurement method provides a new perspective for applying biological silks.

Carbon template (graphene oxide (GO) and carbon fiber (CF)) based magnetic nanomaterials like G-t-F (GO-Fe₃O₄), G-t-FC (GO-CoFe₂O₄), and CF-t-F (CF-Fe₃O₄) were synthesized for this work and successfully incorporated into poly (lactic acid) (PLA) matrix. Saturation magnetism was observed in the ferromagnetic region for synthesized templated materials. PLA-based composites were fabricated by solution casting and filler loading varied in the range of 0.5–2 wt.%. An investigation was conducted on the effects of magnetic filler's nature and structure on the material identities, thermal behaviors, and melt flow properties of the composites. Thermal stability was improved for MC-G-t-F-0.5, and nucleation properties were observed through DSC analysis. Rheology investigations under a magnetic field (current: 0–0.6 A) indicated that the flow behavior of composites is similar to that of magnetorheological fluid. Han plot, Cole–Cole Plot, and Van-Gurp-Palmen plot were studied, and network formation was observed under a magnetic field. Constitutive mechanical models such as Bingham, Casson, and Herschel-Bulkley (HB) were utilized to determine magnetorheological (MR) flow parameters. In the case of a representative magnetic particle nanocomposite, PLA/G-t-F, the dependency of yield stress with G-t-F weight fraction (φ) and magnetic flux density (B) was investigated and recorded. It was observed that composite melt behavior is dependent on the type of magnetic filler, weight fraction, and magnetic flux density.

Organic pollution is a major environmental issue that requires the deployment of steps to lower the organic content of water. In this study, Glycidyl methacrylate (GMA) functionalized Zr-MOF was fabricated and employed as a selective adsorbent in PW to reduce COD level. XRD, EDX, BET, PSA and FT-IR were employed to investigate the properties of the synthesized MOF. The synthesized MOF has an enormous surface area of 1144 m^2/g, a mean pore diameter of 2.84 nm, and an overall pore volume of 0.37 cm³/g. Investigating the effects of pH (2–12), contact time (10–120 min), and adsorbent dose (0-2000 mg/L) on COD % removal allowed us to assess the effectiveness of UiO-66-GMA. The results demonstrated that at pH 8 and a 500 mg/L dose of MOF, COD removal efficiency increased from 35.2 to 94.67%. Additionally, as contact time was extended from 10 to 50 min, the removal efficiency improved from 52.78 to 92.4%. Adsorption isotherm analysis revealed that the pseudo-second-order kinetic and Freundlich isothermal models provided a very good match to the adsorption data (R² = 0.98). A maximum COD removal efficiency of 96.12% was reported. Based on the current research, it is feasible to draw the conclusion that Zr-functionalized MOFs are an efficient adsorbent for the adsorption of organic contaminants.

High-performance pixelated CZT detectors that achieve 3D position sensitivity are promising candidates for use in Compton imaging telescopes. We proposed to use pixelated CZT detectors in the MeV Astrophysical Spectroscopic Surveyor (MASS), which is a large area Compton telescope. Nevertheless, the presence of high-energy protons in space can lead to radiation damage in pixelated CZT detectors, causing their performance to degrade gradually. Using non-ionizing energy loss (NIEL), this study develops a method that quantitatively evaluates the radiation damage of detectors in space. To verify the method, this study irradiated two (2times 2times 1text { cm}^3) pixelated CZT detectors with 100 MeV protons at fluences ranging from (3times 10^7text { p}^+/text {cm}^2) to ( 3times 10^9text { p}^+/text {cm}^2) under two bias sets. When the proton fluence reaches (3 times 10^9 text { p}^+/text {cm}^2), the energy resolution of the detectors significantly deteriorates to (3.8%) at 511 keV (FWHM/E), even after post-correction. Finally, this study provides engineering considerations for their application in space.