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The purpose of this research was to develop glasses that are thermally reflective, radiation-resistant, and mechanically robust. We have synthesized the La(20-x)Pb10B70:Eux series of glasses in this regard. Then, characterization, radiation shielding, structural analysis (Raman, FT-IR, DTA, SEM, XRD, and EDX), dielectrics, thermoluminescence are planned. The XRD and SEM analyses of the test samples reveal a vitreous appearance. The chemical constituents are identified by the EDX analysis in terms of their percentage of atomic weight. The density (2.592 g/cm3) and molar volume (45.44 cm3 mol−1) of the fabricated glass were evaluated as physical properties. The glass transition temperature (approximately 273 °C) and thermal stabilities (0.656 percent) of glasses are determined to be solely dependent on Eu3+ ions, according to DTA investigations. FT-IR and Raman analyses were employed to determine the various structural vibrations of the sample glass. By employing the ultrasonic velocities of the test glasses, an assessment was conducted on the micro-hardness of the glass (5.01 GPa). The shielding characteristics of radiation, such as RPE (31.6 percent) and MAC (16.9 cm2/g), indicate that the shielding behavior is solely the result of the Eu3+ ions. It has been observed that TL properties are examined at gamma irradiation intensities ranging from 5 to 25 kGy. An evaluation was conducted on the frequency factor (3.225 × 1021 S−1) and A.E. (1.785 eV) of glasses. The findings indicate that the TL characteristics of glasses are solely influenced by the Eu3+ ions. Additionally, the investigation of the dielectric properties of glasses was ascertained. The analysis focused on the dielectric constant (8.891), dielectric loss (0.026), ac conductivity (0.735 × 10–8 Ω−1 cm−1), and A.E. (1.051 eV) values of the fabricated glass. The findings suggest that the dielectric properties of glasses are entirely determined by the presence of Eu3+ ions. Overall the LBPE-1.5 glass found to be best in the structural, mechanical, optical, dielectric, radiation shielding and thermoluminescence properties. [ABSTRACT FROM AUTHOR]

The present investigation, aimed to prepare lead silicate glasses doped with samarium ions and to study it's structure, elastic, spectroscopic and thermoluminiscence properties with Al(10−x)Sbx composite influence. The objective of the investigation is to develop TL sustained good laser active resource by means of studying photo and thermoluminiscence properties. In this direction, we have prepared the glass series of Al(10−x)SbxSm0.1Pb30Si59.9 materials (where, 0 ≤ x ≤ 10, with steps of 0, 2, 4, 6, 8 and 10 mol%) after that planned for structural (XRD, FT-IR, DTA, EDS & SEM), Optical (UV & PL) and thermoluminescence characterization. The XRD and SEM studies reveal the glassy behavior of test samples. The EDX analysis signifies the chemical constitutes with atomic weight %. The physical properties such as density and molar volume of glasses were evaluated. The DTA studies of glasses reveal the glass transition and crystallization temperature points. The values of thermal stabilities of glasses found to be purely function of Sb3+ ions. Various structural vibrations of test glass conformed using FT-IR studies. Using ultrasonic velocities of the test glasses, the glasses' micro-hardness was evaluated. From the absorption spectra, the Judd–Ofelt intensity parameters (Ω2, Ω4, Ω6) have been calculated. The PL spectra under stimulation at 402 nm show a prominent reddish–orange emission at 602 nm. The experimental lifetimes (τr) of the 4G5/2 → 6H7/2 (602 nm) luminescence transition were measured using the decay spectral profiles of this transition. The evaluated emission cross-sections (σse), branching ratios (βr), and quantum efficiency (η) allow us to speculate that the lead silicate glasses doped with Sm3+ ions are ideally suitable as potential gain mediums for visible reddish orange lasers pumped directly by readily available 405 nm laser diodes. Quantum efficiencies of the produced glasses are obtained using a decay curve analysis. The emission spectra used to establish the developed glasses' reddish orange emission are used to compute the CIE chromaticity coordinates. It is evident from the stated fluorescent properties that the developed glasses are suited for reddish–orange laser applications, particularly in opto-electronic devices. From all of the values obtained, it can be observed that SAS6 glass code is ideally suited for reddish–orange laser applications. The TL properties are studied at 30 kGy gamma irradiation dose range. The frequency factor and A.E. of glasses were evaluated. This reveals that the TL behavior of glasses is a purely function of Sb3+ ions. Overall, the Al(10−x)SbxSm0.1Pb30Si59.9 glasses prepared are mechanical hard, TL effective, and optically useful resources. [ABSTRACT FROM AUTHOR]

The current research aims to develop an optically active, thermally luminescent, and radiation-shielding glass resources. For that, we have planned to develop a glasses of the chemical composition Ba(25-x)La15Si60Nix (where, 'x' = 0, 0.2, 0.4, 0.6, 0.8 & 1.0 mol%). There after the developed glasses are planned for structure, physical, mechanical, radiation shielding, optical and thermoluminescence characterization. The XRD & SEM studies reveal the glassy behavior. The EDS analysis signifies the chemical constitutes with atomic weight %. The physical properties such as density (~ 2.625 gm/cm3), molar volume (~ 48.48 cm3 mol−1) and refractive index (1.649) of glasses are evaluated. The DTA studies of glasses reveal the GTT (~ 429.5 °C) and thermal stabilities (1.593) evolutions are purely function of Ni2+ ions. Using ultrasonic velocities of the test glasses, the glasses' micro-hardness (~ 2.82 GPa) was evaluated. Radiation shielding properties such as RPE (~ 36.55%) and MAC (~ 16.556) reveal the shielding behavior is purely a function of Ni2+ ions. Using the optical absorption spectra, the bandgap (~ 1.21 eV) of the glasses evaluated. These values also purely function of Ni2+ ions. Using the photoluminescence spectra the luminescence analysis of glasses studied. The variations in values of emission cross section (~ 1.21 × 109, cm2) and Chromacity colour co-ordinates also suggesting emission range of glasses is purely function of Ni2+ ions. The TL properties are studied at 0 and 50 kGy gamma irradiation dose range. The frequency factor (~ 3.062 × 1021, S−1) and A.E. (~ 1.798 eV) of glasses were evaluated. This reveals that the TL behavior of glasses is a purely function of Ni2+ ions. Overall, the NSBL glasses prepared are mechanical hard, TL effective, optical and radiation shielding resources. [ABSTRACT FROM AUTHOR]

The rapidly expanding Himalayan road network connects rural mountainous regions. However, the fragility of the landscape and poor road construction practices lead to frequent mass movements along-side roads. In this study, we investigate fully or partially road-blocking landslides along the National Highway (NH-7) in Uttarakhand, India, between Rishikesh and Joshimath. Based on an inventory of >300 landslides along the ~250 km long corridor following exceptionally high rainfall during September and October, 2022, we identify the main controls on the spatial occurrence of mass-movement events. Our analysis and modeling approach conceptualizes landslides as a network-attached spatial point pattern. We evaluate different gridded rainfall products and infer the controls on landslide occurrence using Bayesian analysis of an inhomogeneous Poisson process model. Our results reveal that slope, rainfall amounts, lithology and road widening are the main controls on landslide occurrence. The individual effects of aggregated lithozones are consistent with previous assessments of landslide susceptibilities of rock types in the Himalayas. Our model spatially predicts landslide occurrences and can be adapted for other rainfall scenarios, and thus has potential applications for efficiently allocating efforts for road maintenance. To this end, our results highlight the vulnerability of the Himalayan road network to landslides. Climate change and increasing exposure along this pilgrimage route will likely exacerbate landslide risk along the NH-7 in the future. [ABSTRACT FROM AUTHOR]

The current research aimed to prepare the Cr2O3 doped Ba(La)2SiO6 glasses and planned for elastic, radiation shielding, electron paramagnetic resonance, and thermoluminescence characterization. The X-Ray diffraction reports reveal the glassy behavior of the pure glass. At the same time, the other test samples show ceramic behavior. Mechanical properties of test samples reveal the range of the microhardness. DTA studies reveal the values of thermal studies of the test samples. After that, the glass-ceramics were tested for radiation shielding properties. The values of mass attenuation coefficient and radiation protection efficiency of the glasses are measured and compared with values obtained with the help of standard photon shielding and dosimetry software. The studies indicate that the glasses developed are capable of radiation shielding. The electron paramagnetic resonance reports suggest high dipole-dipole super-exchange interaction and rhombohedral distortion within the glasses. Furthermore, we have tested the glasses for radiation shielding properties. Upon 50 kGy, γ - irradiation, the thermoluminescence properties of the glasses are reported. The results were exciting and revealed that the resource developed is thermoluminescent at low activation energies. Additionally, the electron paramagnetic resonance and thermoluminescence properties obtained for the glasses are highly interlinked. In this view, to initiate the comprehensive link between electron paramagnetic resonance and thermoluminescence phenomenon, we have annealed the glasses under 0 to 300 °C of temperature and upon the 0 to 50 kGy, γ - irradiation dose level. [ABSTRACT FROM AUTHOR]

The quantification of spatial propagation of extreme precipitation events is vital in water resources planning and disaster mitigation. However, quantifying these extreme events has always been challenging as many traditional methods are insufficient to capture the nonlinear interrelationships between extreme event time series. Therefore, it is crucial to develop suitable methods for analyzing the dynamics of extreme events over a river basin with a diverse climate and complicated topography. Over the last decade, complex network analysis emerged as a powerful tool to study the intricate spatiotemporal relationship between many variables in a compact way. In this study, we employ two nonlinear concepts of event synchronization and edit distance to investigate the extreme precipitation pattern in the Ganga river basin. We use the network degree to understand the spatial synchronization pattern of extreme rainfall and identify essential sites in the river basin with respect to potential prediction skills. The study also attempts to quantify the influence of precipitation seasonality and topography on extreme events. The findings of the study reveal that (1) the network degree is decreased in the southwest to northwest direction, (2) the timing of 50th percentile precipitation within a year influences the spatial distribution of degree, (3) the timing is inversely related to elevation, and (4) the lower elevation greatly influences connectivity of the sites. The study highlights that edit distance could be a promising alternative to analyze event-like data by incorporating event time and amplitude and constructing complex networks of climate extremes. [ABSTRACT FROM AUTHOR]

Intrinsic predictability is imperative to quantify inherent information contained in a time series and assists in evaluating the performance of different forecasting methods to get the best possible prediction. Model forecasting performance is the measure of the probability of success. Nevertheless, model performance or the model does not provide understanding for improvement in prediction. Intuitively, intrinsic predictability delivers the highest level of predictability for a time series and informative in unfolding whether the system is unpredictable or the chosen model is a poor choice. We introduce a novel measure, the Wavelet Entropy Energy Measure (WEEM), based on wavelet transformation and information entropy for quantification of intrinsic predictability of time series. To investigate the efficiency and reliability of the proposed measure, model forecast performance was evaluated via a wavelet networks approach. The proposed measure uses the wavelet energy distribution of a time series at different scales and compares it with the wavelet energy distribution of white noise to quantify a time series as deterministic or random. We test the WEEM using a wide variety of time series ranging from deterministic, non-stationary, and ones contaminated with white noise with different noise-signal ratios. Furthermore, a relationship is developed between the WEEM and Nash–Sutcliffe Efficiency, one of the widely known measures of forecast performance. The reliability of WEEM is demonstrated by exploring the relationship to logistic map and real-world data. [ABSTRACT FROM AUTHOR]

Abstract Glass materials of composition CaO–Y 2 O 3 –B 2 O 3 –P 2 O 5 added with different concentrations of NiO (Ni2+:CYBP) are synthesized by conventional rapid melt quenching method. Various physical properties of these glasses such as polaron radius (r p), molar volume (V m), optical basicity (Λ th) and refractive index (μ) are studied. As an elastic characterization Young's modulus (Y), Poison ratio (σ) and micro hardness (H) of these glasses are studied. These grades suggest that the prepared materials are mechanically hard and exhibiting covalently interlinked structure. Further these samples are characterized by various techniques such as differential thermal analysis, thermoluminiscence, optical absorption, photoluminescence, Ionic conductivity and dielectric dispersion. The thermoluminiscence grades such as peak temperature maximum (T m), shape symmetry factor (μ sf) and activation energies (E τ , E δ and E ω) are studied at various UV irradiation levels. These results strongly recommended that the both electron and hole trap centers were created at the deeper trap levels and contribute higher orders of thermoluminiscence emission with in these glasses subjected to higher orders of temperature and UV irradiation. The various optical absorption and photoluminescence factor's such as, optical band gap (E o), nephelauxetic ratio (β), emission cross section (Ω), branching ratio (ξ) and radiative life times (τ) are studied. These grades found to be maximum for the material which has 0.5 mol% of NiO concentration may be most suggestible for optoelectronic application. The dc and ac conductivity (σ dc & σ ac) of these glasses are estimated. The various dielectric parameter's such as loss tangent (Tan (ϕ)), temperature region of relaxation (ΔT), density of states near Fermi level (N(E f)), activation energies of both dipoles and conduction (E d and E c) are also calculated. These reports clearly disclose that the octahedrally located Ni2+ ions are increasing with increase NiO concentration with in present calcio yttria borophosphate glasses. [ABSTRACT FROM AUTHOR]

Accelerating climate change is causing considerable changes in extreme events, leading to immense socioeconomic loss of life and property. In this study, we investigate the characteristics of extreme climate events at a regional scale to -understand these events' propagation in the near future. We have considered sixteen extreme climate indices defined by the World Meteorological Organization's Expert Team on Climate Change Detection and Indices from a long-term dataset (1951–2018) of 53 locations in Gomati River Basin, North India. We computed the present and future spatial variation of theses indices using the Sen's slope estimator and Hurst exponent analysis. The periodicities and non-stationary features were estimated using the continuous wavelet transform. Bivariate copulas were fitted to estimate the joint probabilities and return periods for certain combinations of indices. The study results show different variation in the patterns of the extreme climate indices: D95P, R95TOT, RX5D, and RX showed negative trends for all stations over the basin. The number of dry days (DD) showed positive trends over the basin at 36 stations out of those 17 stations are statistically significant. A sustainable decreasing trend is observed for D95P at all stations, indicating a reduction in precipitation in the future. DD exhibits a sustainable decreasing trend at almost all the stations over the basin barring a few exceptions highlight that the basin is turning drier. The wavelet power spectrum for D95P showed significant power distributed across the 2–16-year bands, and the two-year period was dominant in the global power spectrum around 1970–1990. One interesting finding is that a dominant two-year period in D95P has changed to the four years after 1984 and remains in the past two decades. The joint return period's resulting values are more significant than values resulting from univariate analysis (R95TOT with 44% and RTWD of 1450 mm). The difference in values highlights that ignoring the mutual dependence can lead to an underestimation of extremes. [ABSTRACT FROM AUTHOR]