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The frequency and intensity of extreme precipitation events are on the rise worldwide. Despite extensive efforts, regional climate models still show significant biases for extreme precipitation events, often due to factors like improper physics, the choice of land surface model, and spatial domain. Thus, this study uses a Coupled Land–Atmosphere Regional Climate Model version 4.7 (RegCM4.7) to explore how the choice of land surface models (LSMs) and domain extent affects the simulation of extreme precipitation over India. In this regard, a total of four sensitivity experiments have been carried out using two LSMs (CLM4.5 and BATS) over each of the two domains (one over the bigger South Asia CORDEX domain and another for the smaller domain over the Indian region). The main objective is to provide a holistic idea for obtaining an optimum model domain and LSMs for precipitation extremes over India. The model performance is demonstrated for extreme precipitation and associated processes. The result shows the systematic discrepancy in simulating extreme precipitation with a strong inter-simulation spread, indicating the strong sensitivity of extreme precipitation on the LSMs as well as the model domain. The BATS configuration shows a significant overestimation of consecutive wet days and very low precipitation, partially associated with a deficiency in convection. By contrast, the considerable underestimation of intense precipitation can be attributed to the presence of frequent, light drizzle, which hinders the accumulation of moisture in the atmosphere to a sufficient degree to prevent extreme rainfall. Despite significant improvement, the best-configured model (CLM with Indian domain) still indicates substantial bias for extreme precipitation. This deficiency in the model could potentially be mitigated by enhancing both horizontal and vertical resolutions. Nevertheless, further research is needed to explore other physics parameterizations and dynamic mechanisms to address this issue. [ABSTRACT FROM AUTHOR]

In this work, the activated carbon (AC) is derived from the waste material of peanut shells. The obtained activated carbon has been synthesized using the chemical activation process via impregnation with NaOH at various proportions (1:2 and 1:3). The structural, morphological, and electrochemical properties of obtained AC are examined by X-ray diffraction (XRD), BET surface analysis, scanning electron microscopy (SEM), and electrochemical techniques. The resulting AC shows the enhancement in specific surface area (SSA) from 584 to 735 m2/g at 1:2 ratio and 826 m2/g at 1:3 ratio after the activation process. The electrodes are fabricated using derived activated carbon for electrochemical characterization. It has been observed through cyclic voltammetry and galvanostatic charge–discharge measurements that 1:3 NaOH-activated samples reveal the maximum value of specific capacitance (263 F/g at 10 mV/s and 290 F/gat 0.2A/g). The sample also conveys the pre-dominant ~ 98% of efficiency from 400 to 1000th cycle with fast and almost constant capacitance. The electrochemical impedance spectroscopy (EIS) result suggests the pure capacitive nature of the sample and indicates the dominating electric double-layer capacitive (EDLC) behavior. The obtained results demonstrate that the peanut shell–derived activated carbon is a potential candidate as an electrode material for supercapacitors. [ABSTRACT FROM AUTHOR]

Chemical warfare agents (CWAs) have become a pivotal concern for the global community and spurred a wide spectrum of research for the development of new generation protective materials. Herein, a highly effective self-detoxifying filter consisting of in-situ immobilized Zirconium hydroxide [Zr(OH)4] over woven activated carbon fabric [Zr(OH)4@W-ACF] is presented for the removal of CWAs. It was prepared to harness the synergistic effect of high surface area of W-ACF, leads to high dispersion of CWAs and high phosphilicity and reactivity of [Zr(OH)4]. The synthesized materials were characterized by ATR-FTIR, EDX, SEM, TEM, XPS, TGA, and BET surface area analyzer. The kinetics of in-situ degradation of CWAs over Zr(OH)4@W-ACF were studied and found to be following the first-order reaction kinetics. The rate constant was found to be 0.244 min−1 and 2.31 × 10−2 min−1 for sarin and soman, respectively over Zr(OH)4@W-ACF. The potential practical applicability of this work was established by fabricating Zr(OH)4@W-ACF as reactive adsorbent layer for protective suit, and found to be meeting the specified criteria in terms of air permeability, tearing strength and nerve agent permeation as per TOP-08-2-501A:2013 and IS-17380:2020. The degradation products of CWAs were analyzed with NMR and GC–MS. The combined properties of dual functional textile with reactive material are expected to open up new exciting avenues in the field of CWAs protective clothing and thus find diverse application in defence and environmental sector. [ABSTRACT FROM AUTHOR]

The performance of vertical parameterization schemes, namely, turbulent kinetic energy (TKE) and K-profile parameterization (KPP), is evaluated over the domain [30E-120E; 20S-30N] in the Indian Ocean using the Nucleus for European Modeling of the Ocean (NEMO) regional model. The surface and sub-surface hydrography and mixed layer depth (MLD) of the simulations using TKE and KPP schemes have been compared. The KPP scheme produces higher bias (∼0.5 °C) of sea surface temperature (SST) in monsoon and post-monsoon seasons, which reduces on using the TKE scheme. The maximum surface salinity difference (0.45 psu) between TKE and KPP simulations is obtained over the head Bay of Bengal (BoB) in the post-monsoon months. The KPP scheme also overestimates MLD of the region. Barring highly convective regions as well as regions marked with very low and rapidly changing salinity, the TKE scheme performs better than KPP scheme in simulating the hydrography and MLD of the region. The differences between TKE and KPP simulations in the vertical stability and mixing are studied using buoyancy frequency, vertical shear of horizontal currents and energy required for mixing as quantifiers. The mixed layer heat budget analysis explains seasonal variability of SST and differences in vertical mixing parameterizations. [ABSTRACT FROM AUTHOR]

Present work deals with the experimental and computational investigation of thermal properties and fluid flow characteristics on circular tube with elliptical inserts. The major axis is taken equal to hydraulic diameter i.e. 6.81cm. A new parameter, height ratio (γ = b/D) has been defined with three values – 0.45, 0.66, and 0.74. The test section is 1.5 m long which is provided with a constant heat flux of 1000 W/m2 along with air as working fluid at Reynolds number ranging from 3,000 to 21,000. The results show that the augmentation in heat transfer was six times for case γ = 0.74 and the maximum thermal performance factor (TPF) obtained is 2.43 for insert with γ = 0.45 at Re = 3000 over the smooth tube. Computational fluid dynamics (CFD) investigation is also carried out for elliptical inserts, and the results are in good agreement with the experimental results where the maximum deviations in Nusselt number, friction factor, and TPF are ±9.39, ±8.68, and ±8.58%, respectively. CFD investigation for tube having circular inserts with vertical twisted tapes (CVTT) and elliptical inserts with vertical twisted tapes (EVTT) is also presented where the augmentation in heat transfer ranges 3–8 times for CVTT placed in full length and TPF is ranging 1.19–2.63 times for CVTT placed in TL length over to smooth tube. [ABSTRACT FROM AUTHOR]

A very efficient, solvent-free thionation of amides, lactams, ketones, xanthones and acridone with PS[Cl.sub.3]/[H.sub.2]O/[Et.sub.3]N is described. A variety of thiocarbonyl compounds can be achieved through this method under solventless condition with microwave irradiation.