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In this study, we have synthesized solid polymer electrolytes using polyvinyl alcohol as a host polymer that has been doped with ionic liquid and ammonium iodide. Impedance spectroscopy revealed that the increase in ionic liquid doping increased the ionic conductivity of the PVA‐NH4I complex. The crystalline nature of the polymeric films was studied using polarized optical microscopy and x‐ray diffraction. To confirm the blending ability of polymer electrolyte, Fourier transform infrared spectroscopy was also used. Finally, a supercapacitor was fabricated using the highest conducting IL‐doped polymer electrolyte which demonstrates a specific capacitance of 97 F/g with a stable efficiency. [ABSTRACT FROM AUTHOR]

The primary goal of this study is to synthesize a high‐conducting polymer electrolyte film. The PVDF‐HFP and NaSCN film are prepared which showed the highest conductivity at 30 wt% dopant of NaSCN in the Polymer PVDF‐HFP which is 1.24× 10−4 S cm−1. Therefore, here the base polymer is taken as PVDF‐HFP and NaSCN (30 wt%) and further Acetylene Black is added to check the variation in the conductivity of the polymer film. Solution casting technique is used to create solid polymer electrolyte films using poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP) with salt sodium thiocyanate and Acetylene Black. Polarized optical microscopy (POM) is used to evaluate the morphology of the polymer film surface. Fourier transform infrared spectroscopy (FTIR) to check the presence of functional group is used, impedance spectroscopy is used for the measurement of the conductivity of the sample, linear sweep voltammetry for finding electrical stability window, and transference number measurements for concentration of charge carriers are done for the electrical studies of polymeric films. The 1 wt% Acetylene Black doped polymer electrolyte film is found to have the maximum ionic conductivity, which is 1.95 × 10−3 S cm−1. The solid polymer electrolyte film has an electrochemical stability window (ESW) of 4.8 V and tion value of 0.83. [ABSTRACT FROM AUTHOR]

In recent scenarios, plenty of research has been conducted on porous activated carbon derived from biowaste precursors. The well‐developed surface area and porous nature of biowaste‐derived activated carbon material make them good candidates for electrochemical devices to use as electrode material. In the present work, we have used waste peanut shells (W.P.) as a precursor material to derive large surface area activated carbon. Chemical activation is used to activate the activated carbon, for which ZnCl2 is used as an activating agent. The waste peanut shell‐derived activated carbon (WPAC) is studied via XRD, FESEM, and BET. Prepared carbon shows a large BET surface area of 1366 m2 g−1 and a well‐developed pore structure; the presence of pores is also confirmed by FESEM images. A solid‐state supercapacitor is also fabricated using waste peanut shell‐based activated carbon and ionic liquid‐based polymer electrolyte. The EDLC is further studied using electrochemical characterizations such as CV, EIS, and GCD. The EIS study found that the WPAC‐based EDLC cell shows a specific capacitance of 25 F/g at 10 mHz. A DSSC is also fabricated using the WPAC on the counter electrode, and it shows an efficiency of 0.96% with a fill factor of 27.79. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol‐based polymeric films with NaI and ionic liquid (1‐Butyl‐1‐methylpyrrolidinium hexafluorophosphate) have been developed by using the solution cast method. The produced polymer electrolyte sheets were evaluated using various methods. Electrochemical impedance spectroscopy was utilized to measure the conductivity of the polymeric films, and the ionic liquid doped films showed an increase with a maximum at 6 wt% ionic liquid with a value for conductivity of 4.545 × 10−4 S cm−1. The morphological features of the most conductive polymer were further investigated using polarized optical microscopy and x‐ray diffraction. Ionic doping causes an increase in the amorphous nature. Using Fourier transform infrared spectroscopy, an excellent complexity between PVA, salt NaI, and ionic liquid was assessed. Thermogravimetric analysis was used to inspect the polymer films' thermal stability. The highest conducting sample was used for manufacturing an electric double‐layer capacitor. The behavior of manufactured electric double‐layer capacitor has been evaluated through EIS, CV, and GCD. [ABSTRACT FROM AUTHOR]

Plastics are widely used synthetic materials in various industries worldwide. The abundance of plastics, which are mainly carbon‐based polymers, has led to a significant accumulation of plastic waste in landfills and the environment due to their durability and affordability. Although plastic pollution of the oceans has been known for many years, there is still limited knowledge about the composition, distribution, impact, and fate of plastic waste in the environment. In this review, the focus is on environmental pollution by plastics, highlighting the source (feedstock) and degradation behavior of these materials. The goal is to provide insights for material design strategies that address the management of plastic waste at the end of its life cycle. The authors argue that the development of materials labeled marine biodegradable or universally biodegradable is not a sufficient solution on its own to address plastic pollution. Instead, it is critical to incorporate practical plans for recovery and treatment into material and product design principles. These plans should be based on existing systems or possibly developed in parallel. In summary, this article highlights the widespread pollution of the environment by plastics and emphasizes the need for comprehensive material design strategies that include not only biodegradability but also practical recovery and treatment methods. By considering the entire lifecycle of plastics, we can work to reduce the harmful impact of plastic waste on our planet. [ABSTRACT FROM AUTHOR]

At the time, the world critically requires renewable energy. The challenge is figuring out how to meet expanding global energy consumption. Dye‐sensitized solar cells (DSCs) have attracted a lot of interest due to their high energy conversion efficiency, low cost, environmental friendliness, and easy production procedure. First, the study prepares standard cell platinum, which is the most expensive and in low supply. By replacing PVC‐derived porous carbon for expensive platinum in the DSScs counter electrode. The standard efficiency of platinum counter electrode comes out to be 1.94 and efficiency of PVC derived porous carbon electrode comes out to be 0.46. [ABSTRACT FROM AUTHOR]

Transformation of CO2 into value‐added chemicals remains a key challenge. Herein, nonthermal plasma (NTP)‐activated CO2‐H2O conversion over BaTiO3‐mixed NiO/CeO2 (Ni/Ce+) and Co3O4/CeO2 (Co/Ce+) catalysts is demonstrated. In a continuous‐flow dielectric barrier discharge reactor and under ambient conditions, optimum Co/Ce+ showed formation rates of CO and O2 of (43.6 ± 3.1) and (20.8 ± 0.7) μmol g−1h−1, respectively. CO2 conversion was found to be dependent on a combination of the basicity of the catalyst surface, CO2 flow rate, plasma input power, and relative humidity. Subsequently, kinetic analysis suggested that the activation energies over Ni/Ce+, Co/Ce+, and NiCo/Ce+ are 35.68, 15.61, and 25.88 kJ mol−1, respectively. By combining these findings, a plausible reaction mechanism that can facilitate understanding the trend of product formation is also provided. [ABSTRACT FROM AUTHOR]

Transformation of CO2 into value‐added chemicals remains a key challenge. Herein, nonthermal plasma (NTP)‐activated CO2‐H2O conversion over BaTiO3‐mixed NiO/CeO2 (Ni/Ce+) and Co3O4/CeO2 (Co/Ce+) catalysts is demonstrated. In a continuous‐flow dielectric barrier discharge reactor and under ambient conditions, optimum Co/Ce+ showed formation rates of CO and O2 of (43.6 ± 3.1) and (20.8 ± 0.7) μmol g−1h−1, respectively. CO2 conversion was found to be dependent on a combination of the basicity of the catalyst surface, CO2 flow rate, plasma input power, and relative humidity. Subsequently, kinetic analysis suggested that the activation energies over Ni/Ce+, Co/Ce+, and NiCo/Ce+ are 35.68, 15.61, and 25.88 kJ mol−1, respectively. By combining these findings, a plausible reaction mechanism that can facilitate understanding the trend of product formation is also provided. [ABSTRACT FROM AUTHOR]

In solid–solid composite formation by dispersal of insulating filler in an ionic matrix results in ionic conductivity enhancement which has been discussed in details in this paper. Present system deals ammonium oxalate ((NH4)2C2O4·1H2O) dispersed with insulating filler (Al2O3). Electrical, structural, and thermal studies viz. conductivity measurement, ion transport, ionic transference number, infrared spectroscopy, and differential scanning calorimetry are presented in detail. [ABSTRACT FROM AUTHOR]

Due to increasing energy demand day by day, it must be necessary to have an alternate source of energy beside natural resources. Sun is the ultimate source of solar energy. So, from this solar energy, various types of solar cells are fabricated easily which are available in markets but these are somewhat costly. So, there is requirement of a low‐cost alternative to costly crystalline solar cells, which is fulfilled by dye sensitized solar cell (DSSC). Due to many potential properties like good ionic conductivity, thin film forming ability and many more, polymer electrolyte plays a vital role in improving the efficiency of DSSC which cannot be obtained by using volatile liquid electrolytes which are used earlier. The reliance of DSSCs on liquid electrolytes imposes a limit and restriction on the manufacture of DSSC modules. Liquid electrolyte faces many problems like corrosion, leakage, and evaporation. When the photoanode comes into touch with the volatilized redox‐electrolytes solution, the charge distribution at the semiconductor–electrolyte interface changes, resulting in photo corrosion on the photoelectrode. Furthermore, electron recombination at semiconductor–liquid electrolytes interfaces is discovered to cause performance losses. The concept of ionic conductivity observed in polymer materials when complexed with salt is a significant step forward in the development of DSSC devices. In this review, the fabrication of DSSC using polymer electrolyte, specifically PVA based solid polymer electrolyte is discussed. Here solid polymer electrolytes are of special interest due to thin film forming ability and overall good performance. Due to inherent properties like cost‐effectiveness, better tensile strength, and high hydrophilicity, PVA is chosen as a novel applicant for host polymer. The recent advancement of DSSC using modified PVA polymer electrolyte by incorporation of nanosized fillers, plasticizers, polymer blend, by the formation of conducting polymer electrolyte are discussed in detail. The improvement in ionic conductivity and enhanced efficiency of DSSC by using above mentioned factors are also discussed. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have appeared as a leading next‐generation photovoltaic technology. However, notwithstanding rolling efficiencies, many questions remain unreciprocated regarding the mechanisms and performance of the operation. Solution‐processed organic‐inorganic hybrid perovskites have fascinated attention as light‐harvesting materials for perovskite solar cells and photonic applications. The present study focuses on the optical and electronic study of CH3NH3PbBr3 and CH3CH2NH3PbI3 perovskite fabricated by a one‐step solution‐based self‐assemblage method. It is seen that in this study, methyl group represents a better performance than ethyl‐based perovskite‐sensitized solar cells (PSSCs). All the studies centralize on electro‐optical properties of efficient CH3CH2NH3PbI3 and CH3CH2NH3PbI3 PSSC based on polymer electrolytes. It has also characterized lab synthesized perovskite samples by scanning electron microscopy (SEM), UV–vis spectrophotometer, and photovoltaic performance of lab fabricated PSSC is measured by Keithley 2400 resource meter. These findings establish systematic strategy rules to attain silicon‐like efficiencies in simple perovskite solar cells. [ABSTRACT FROM AUTHOR]

Solid polymer electrolyte films blended with ionic liquid 1‐ethyl‐3‐methylimidazolium tricyanomethanide (EMImTCM) and poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVdF‐HFP) are prepared via solution cast technique. The physical characterization of polymeric film is performed by X‐ray diffraction (XRD), polarized optical microscopy (POM), Fourier transform infrared spectroscopy (FTIR), and thermo‐gravimetric analysis (TGA) studies. The gel electrolyte film with 300 wt% of IL shows the high ionic conductivity value of 3.7 × 10−2 S cm−1, and operating voltage from −0.5 to 1.5 V, i.e., electrochemical stability window (ESW) ≈ 2.0 V. The dielectric properties of the polymeric films such as dielectric constant, dielectric loss tangent (Tan δ), relaxation frequency, and time are evaluated. [ABSTRACT FROM AUTHOR]

Immune dysregulation is critical in vitiligo pathogenesis. Although the presence and roles of numerous CD4+ T‐cell subsets have been described, the presence of Th9 cells and more importantly, roles of IL‐9 on melanocyte functions are not explored yet. Here, we quantified the T helper cell subsets including Th9 cells in vitiligo patients by multicolor flowcytometry. There was an increased frequency of skin‐homing (CLA+) and systemic (CLA‐) Th9 cells in vitiligo patients compared to healthy donors. However, there was no difference in Th9 cell frequency in vitiligo patients with early and chronic disease. There was negligible IL‐9 receptor (IL‐9R) expression on human primary melanocytes (HPMs); however, IFNγ upregulated IL‐9R expression on HPMs. Functionally, IL‐9/IL‐9R signaling reduced the production of IFNγ‐induced toxic reactive oxygen species (ROS) in HPMs. There was no effect of IL‐9 on expression of genes responsible for melanosome formation (MART1, TYRP1, and DCT), melanin synthesis (TYR), and melanocyte‐inducing transcription factor (MITF) in HPMs. In conclusion, this study identifies the presence of Th9 cells in vitiligo and their roles in reducing the oxidative stress of melanocytes, which might be useful in designing effective therapeutics. [ABSTRACT FROM AUTHOR]

In this paper, a blind symbol timing offset (STO) estimation method is proposed for offset quadrature phase‐shift keying (OQPSK) modulated signals, which also works for other linearly modulated signals (LMS) such as binary‐PSK, QPSK, π/4‐QPSK, and minimum‐shift keying. There are various methods available for blind STO estimation of LMS; however, none work in the case of OQPSK modulated signals. The popular cyclic correlation method fails to estimate STO for OQPSK signals, as the offset present between the in‐phase (I) and quadrature (Q) components causes the cyclic peak to disappear at the symbol rate frequency. In the proposed method, a set of close and approximate offsets is used to compensate the offset between the I and Q components of the received OQPSK signal. The STO in the time domain is represented as a phase in the cyclic frequency domain. The STO is therefore calculated by obtaining the phase of the cyclic peak at the symbol rate frequency. The method is validated through extensive theoretical study, simulation, and testbed implementation. The proposed estimation method exhibits robust performance in the presence of unknown carrier phase offset and frequency offset. [ABSTRACT FROM AUTHOR]

The southern Indian state of Kerala experienced exceptionally high rainfall during August 2018, which led to devastating floods in many parts of the state. Prediction and early warning of severe weather events in vulnerable areas is crucial for disaster management agencies in order to protect life and property. In recent years, state‐of‐the‐art numerical weather prediction (NWP) models have been used operationally to predict rainfall over different spatial and temporal scales. In the present paper, predictions based on the National Centre for Medium Range Weather Forecasting (NCMRWF) models (NCUM, NCUM‐R and NEPS) are assessed over Kerala to demonstrate the capabilities of high‐resolution models. It is found that the deterministic NWP model (NCUM and NCUM‐R) forecasts are accurate at shorter lead times (up to Day 3) mainly in terms of timing and, to some extent, intensity. At higher lead times (beyond Day 3), the ensemble‐based probabilistic forecasts are useful and actionable. [ABSTRACT FROM AUTHOR]

DNA damage‐inducible 1 (Ddi1) is a multidomain protein with one of the domains being retropepsin‐like. HIV‐1 protease inhibitors were found to reduce opportunistic infections caused by pathogens like Leishmania and Plasmodium, and some of them were shown to inhibit the growth of these parasites. In Leishmania, Ddi1 was identified as a likely target of the inhibitors. We report the crystal structure of the retropepsin‐like domain of Ddi1 from Leishmania major as a dimer with clear density for the critical ‘flap’ region. We have characterized binding with one of the HIV‐1 protease inhibitors in solution using bio‐layer interferometry and by docking. Further, we have performed molecular dynamics (MD) simulation studies that show that the protein undergoes a conformational change from open to semi‐open and closed forms with the closing of the flexible flap over the active site. [ABSTRACT FROM AUTHOR]

Abstract: The application of Mg for hydrogen storage is hindered due to the slow absorption of hydrogen in Mg films. Herein, the hydrogenation process is explored theoretically using density functional theory calculations, and energy barriers are compared for hydrogen diffusion through Pd nanoparticle/Mg film interfaces and their variations, i.e., Pd(H)/Mg(O). Decomposing the mechanism into basic steps, it is shown that Pd undergoes a strain‐induced crystallographic phase transformation near the interface, and indicated that hydrogen saturation of Pd nanoparticles enhances their efficiency as nanoportals. Using energetic arguments, it is explained why hydrogen diffusion is practically prohibited through native Mg oxide and seriously suppressed through existing hydride domains. Hydrogen flux is experimentally investigated through the nanoportals in Pd‐nanoparticle decorated Mg films by pressure‐composition isotherm measurements. An r ≈ t1/3 relationship is theoretically calculated for the radial growth of hemispherical hydride domains, and this relationship is confirmed by atomic force microscopy. The diffusion constant of hydrogen in Mg films is estimated as DHfilm ≈ 8 × 10−18 m2 s−1, based on transmission electron microscopy characterization. The unique nanoportal configuration allows direct measurement of hydride domain sizes, thus forming a model system for the experimental investigation of hydrogenation in any material. [ABSTRACT FROM AUTHOR]

We examined a mixture of magnetite (Fe3O4) and iron (Fe) as a possible CO2 sorbent easily applicable for any ironmaking industries. The mixture reacts with CO2 to form siderite (FeCO3). Our experimental results illustrate a capture capacity of 7.98 mmol [ABSTRACT FROM AUTHOR]

The Indian Monsoon Data Assimilation and Analysis (IMDAA) is a regional high‐resolution atmospheric reanalysis over the Indian subcontinent. This regional reanalysis over India is the first of its kind and is produced by the National Centre for Medium Range Weather Forecasting and Met Office, UK, in collaboration with the India Meteorological Department under the National Monsoon Mission project of the Ministry of Earth Sciences, Government of India. The reanalysis runs from 1979 to 2018, to span the era of modern meteorological satellites. This article briefly describes the IMDAA system and discusses the performance of the IMDAA during summer monsoon (June–September). This study provides evidence for substantial improvements seen in IMDAA compared to the ERA‐Interim reanalysis fields over India. The evaluation is carried out for the period of 1979–1993 for all major features associated with the Indian Monsoon to highlight improvements compared to ERA‐Interim and to document the biases. The study also demonstrates the potential use of the IMDAA data for applications such as wind resource assessment over India. Key Points: IMDAA data are based on high‐resolution (12 km) regional atmospheric reanalysis using the latest methodologies in data assimilationThe advanced data assimilation methods used in IMDAA allow large amounts of data from the satellites and ground‐based observationsIMDAA forms the best analysis data at high grid resolution (12 km) over the Indian monsoon region [ABSTRACT FROM AUTHOR]