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Nanocomposite, which comprise organic and inorganic materials have gained increasing interest in the application for enhanced sensing response to both reducing and oxidation gases. In this study, a nanocomposite is chemical polymerization synthesized by reinforcing Ag nanoparticles with different concentration doped into the matrix of Polypyrrole (PPy). This nanocomposite is used as a sensing platform for ammonia detection with different concentration (ppm). The homogeneous distribution of Ag nanoparticles onto the PPy matrix provides a smooth and dense surface area, further accelerating the transmission of electrons. The synergistic effect of PPy@Ag matrix is responsible for the outstanding conductivity, compatibility and catalytic power of the proposed gas sensor. The structure, morphology, and surface composition of as-synthesized samples were respectively, examined via X-ray diffraction, field emission scanning electron microscopy, Ultraviolet-visible spectroscopy, Thermogravimetric analysis and Fourier transform infrared spectroscopy. The results indicated that sensor based on the PPy@Ag5 (2 gm) nanocomposite showed the highest response toward ammonia as compare to pure PPy at room temperature with a response value is 58 % to 100 ppm. Overall, the obtained findings demonstrated that the PPy@Ag nanocomposite are promising materials for gas sensing applications in environmental monitoring.

Here we present a novel study of Calcium hydroxide and iron-nickel co-doped Calcium hydroxide nanoparticles. Calcium hydroxide (CH) and iron-nickel doped Calcium hydroxide (INCH) nanoparticles (NPs) were synthesized by a simple chemical precipitation method. XRD, FESEM-EDX, and FTIR were used to characterize the structural and morphological characteristics, while UV–Vis spectroscopy was used to study the optical alterations. The average crystallite size is estimated to be 63.75 nm and 66 nm for the CH and INCH nanoparticles, respectively. The FESEM analysis revealed that CHNPs form a hexagonal-like shape, whereas INCH NPs produce highly agglomerated dispersed particles. The UV–Vis spectroscopy revealed that the band gap changes with average crystallite size concurrently.

Manganese dioxide-multiwall carbon nanotube (MnO2-MWCNT) nanocomposites were synthesized via one-pot synthesis method with varying concentrations of 1 mg/ml, 4 mg/ml, and 10 mg/ml MWCNT. The synthesized nanocomposites were characterized using x-ray diffraction (XRD), transmission electron microscopy (TEM), and electrochemical measurements. The intent of studying different concentrations is, ultimately, to correlate the effect of the concentration of multiwall carbon nanotube on the electrochemical performance of the MnO2-MWCNT nanocomposites. Two primary phenomena were observed as CNT concentration increased. First, less crystalline MnO2 adsorption onto individual CNTs occurred. Subsequently, CNT agglomeration became the primary feature of the nanostructures of high CNT concentration. The electrochemical studies reveal that the specific capacitance of MnO2 increases from 124 F/g to 145 F/g by the addition of 1 mg/ml MWCNTs and decreases to 102 F/g for MnO2-10 mg/ml MWCNT nanocomposite.

Oblique ion beam patterned and structured thin films hold promise as an advanced material for applications to photonics, micro- to nano-electronics, electro-optical and electrochemical devices fabrication. Herein, for the first time, we report the fabrication of patterned and structured SiC thin films over Si(111) by obliquely incident Ar+ beam. We show that at a short time scale, carbon clusters possessing nano-dimensional size evolve while ripple structures with direction parallel to the ion beam projection emerge at later time scales. The roughness evolution plot follows exponential and power law scaling at low and high bombarding time (in terms of ion fluence). The underlying mechanism is the altered surface layer composition due to the non-stoichiometric sputtering of silicon and carbon. The optical bands corresponding to silicon carbide (3.27–4.23 eV) & silicon (1.15–1.45 eV) co-exist for lower argon ion fluences while optical bands of silicon (1.15- 1.45 eV) remains and silicon carbide vanishes for higher argon ion fluences. Our experimental findings demonstrated the fabrication of ripple patterns over radiation tolerant, thermally and physically stable SiC by large area irradiation and capability to tailor the temporal characteristics of these evolved structures.

We have prepared CuS and CuS-rGO nanocomposites via the hydrothermal method. The physical properties of the synthesized materials were studied through x-ray diffraction and scanning electron microscopy. The supercapacitor characteristics were evaluated by cyclic voltammetric and galvanostatic charge–discharge studies. The cyclic voltammetric studies conform the pseudocapacitive nature of CuS and CuS-rGO electrodes. The specific capacitance of CuS was obtained as 207, 150, and 97 F/g at a current density of 0.5, 5, and 20 A/g, respectively. The rGO-CuS nanocomposite showed improved specific capacitance of 350, 251, and 149 F/g at current densities of 0.5, 5, and 20 A/g, respectively.

Skin radiation exposure occurs during planned or unplanned radiation events, such as radiotherapy or nuclear radiation accidents, respectively, resulting into acute and chronic effects depending upon the extent of the radiation exposure or contamination. Radioactive nuclide-induced contaminations severely affect the human skin as skin is the largest organ of the body. Skin radioactive contamination may result into radiation-induced burns that may significantly cause morbidity without any medical intervention. In such scenario, it is necessary to provide priority to severe and life-threatening injuries. The current review provides a holistic picture about the mode of occurrence of radiation injuries, types of radiation burns, local skin effects and pathophysiology, prognosis, diagnosis and treatment, and challenges in the management of radiation wounds. Further, the review also includes the dressings used for irradiated wounds and comparison of amniotic and silver dressings, which possess potential bactericidal and wound-healing properties.

Summary: Cubic spinel LiMn2O4 (LMO) are promising electrode materials for advanced technological devices owing to their rich electrochemical properties. Here, a series of Gd3+-doped LiMn2O4 were synthesized using a simple one-step sol-gel synthesis, and a systematized study on the effect of increasing Gd3+ concentration on magnetic properties is conferred. The Raman and density functional theory (DFT) calculations of the synthesized materials were correlated with the magnetic properties; we observed a high coercivity value for the doped LMO compared to pristine LMO, which scales down from 0.57T to 0.14T with an increase in Gd concentration. The samples exhibited paramagnetic (at 300K) to antiferromagnetic (at 5K) transition and variation in the magnetic moment due to the replacement of Mn+2 or Mn+3 ion by Gd+3 ion from the octahedral 16d lattice site. The observed phase transitions in the hysteresis curve below the Neel temperature (TN) at 5K are found to be due to the superexchange mechanism.

Metal-matrix nanocomposites have a separate variety of objectives under provisions of their enhanced properties. Ion irradiation with low energy is a curious contrivance to achieve the bulk variations of distinct materials. The effect of low energy ion irradiation is explored on Cu-C60 nanocomposite thin films grown by the thermal co-deposition method. The Cu concentration in the as-deposited sample is found to be ∼ 45 at.% by Rutherford Backscattering Spectrometry (RBS). Owing to high metal concentration, a Surface Plasmon Resonance (SPR) peak is found at 616 nm in the as-deposited sample and the average size of Cu nanoparticles is determined to be ∼7.8 nm, with a broad size distribution. The as-deposited samples are irradiated with a beam of 220 keV Ag ions using an ion accelerator, which leads to moderate variations in the structural, electrical, and optical properties of nanocomposite thin film. The SPR peak is effectively red-shifted by ∼16 nm at a highest dose. The outcomes of Raman spectroscopy disclose the gradual transformation of fullerene C60 into amorphous carbon with increasing doses. High-Resolution Transmission Electron Microscopy (HRTEM) images demonstrate the minor growth of copper nanoparticles with ion irradiation. A growth in surface grains with ion dose is confirmed by Field Emission Scanning Electron Microscope (FESEM) and Atomic Force Microscopy (AFM). The X-ray Photoelectron Spectroscopy (XPS) measurements have been used for the chemical state evaluation of the nanocomposite films. The I-V measurements show the conversion of fullerene into amorphous carbon with a loss in the resistivity of the film.

Composites of MnO2/multi-wall carbon nanotubes (MWCNTs) were prepared using different weight ratios of MWCNTs: KMnO4 (1:2, 1:5, 1:10, 1:15, 1:20, and 1:25) using a one-pot hydrothermal method. The synthesized materials were physically characterized by x-ray diffraction, transmission electron microscopy (TEM), field emission-scanning electron microscopy (FE-SEM), (Brunauer–Emmett–Teller) BET, and thermogravimetric analysis. TEM and SEM studies indicate that MnO2 is homogeneously entangled with MWCNTs. The electrochemical performance evaluation was performed in a 3-electrode system using MnO2/MWCNT electrodes coated onto a Ni mesh as the working electrode, a Pt foil as the counter electrode, and Ag/AgCl as the reference electrode. The specific capacitance was obtained from charge–discharge studies at varying current densities between 0.5 and 5 A/g. The specific capacitance of MWCNT-KMnO4 (1:10, 1:15, and 1:25) samples was obtained as 114, 164, and 100 F/g, respectively, at a current density of 1 A/g.

This paper demonstrates the fabrication of a thin film of Zinc Oxide (ZnO) by RF sputtering on Indium Tin Oxide (ITO) substrate for Resistive Random-Access Memory (RRAM) application. The fabricated ZnO/ITO sample was bombarded with Swift Heavy Ion (SHI) of Ag9+ ions at 100 MeV with the fluence of 1 × 1013 ions/cm2 to study the effect of ion irradiation on the resistive switching of ZnO based RRAM. The resistance ratio of Au/ZnO/ITO-based devices was measured after ion irradiation. Enhancement of more than 100% in resistance ratio was observed in I-V measurements, while in pristine sample approximately linear switching was observed. The fabricated samples were characterized using Atomic Force Microscopy (AFM) and X-Ray Diffraction (XRD) to study the structural and morphological properties. The chemical composition of the ZnO/ITO substrate was studied using Rutherford Backscattering Spectrometry (RBS) spectrum analysis. The current study demonstrates that ion irradiation improves the performance of ZnO-based RRAM devices significantly. The ZnO based RRAM with enhanced resistive switching can find applications in memory devices for low power scalable devices.

Installation of telecom towers in remote areas especially in developing countries like India is a major problem for telecom industries because of the unavailability of reliable power supply. The grid supply is not regular in these countries and up to some extent, they are dependent on diesel generators for power supply. But these diesel generators have some major issues such as high operating cost due to high cost of fuel, transportation cost of fuel, high maintenance cost, and these diesel generators also emits pollution to the environment. In presented work, an approach has been proposed for telecom companies for providing power supply to their telecom towers. An economic cost analysis has been proposed by considering various criteria such as cost, air & noise pollution and reliability, etc. Some power supply alternatives including unconventional and hybrid of conventional and unconventional alternatives have been compared to find the solution such as diesel-powered telecom towers, solar powered telecom towers, and their hybrids. The main objective of this work is to provide a reliable, cost effective and environment friendly Remote Area Power Supply (RAPS) system for a particular site in India (Uttar Pradesh). A number of criteria are involved in discussed problem in order to select an effective power supply source. Therefore, the problem has been considered as a Multi Criteria Decision Making (MCDM) problem. To select the best alternative, a Fuzzy AHP and TOPSIS based approach has been proposed. Fuzzy AHP (Analytic Hierarchy process) has been used for calculating the weightage of criteria and the concept of Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) has been applied for ranking the alternatives. The results give assured reliability and sustainability for remote areas using a solar photovoltaic (PV)-diesel generator hybrid energy system.

The green, sustainable, and inexpensive creation of novel materials, primarily nanoparticles, with effective energy-storing properties, is key to addressing both the rising demand for energy storage and the mounting environmental concerns throughout the world. Here, an orange peel extract is used to make cobalt oxide nanoparticles from cobalt nitrate hexahydrate. The orange peel extract has Citrus reticulata, which is a key biological component that acts as a ligand and a reducing agent during the formation of nanoparticles. Additionally, the same nanoparticles were also obtained from various precursors for phase and electrochemical behavior comparisons. The prepared Co-nanoparticles were also sulfurized and phosphorized to enhance the electrochemical properties. The synthesized samples were characterized using scanning electron microscopic and X-ray diffraction techniques. The cobalt oxide nanoparticle showed a specific capacitance of 90 F/g at 1 A/g, whereas the cobalt sulfide and phosphide samples delivered an improved specific capacitance of 98 F/g and 185 F/g at 1 A/g. The phosphide-based nanoparticles offer more than 85% capacitance retention after 5000 cycles. This study offers a green strategy to prepare nanostructured materials for energy applications.

Probe-fed hexagonal patch antenna suffers from impedance mismatch especially when feed is located at one of the vertices of polygon. Hexagonal planar antennas also suffer from high cross polar levels. This paper proposes a method to overcome impedance mismatch and to increase co-polarization level by reducing ground plane. Vertex feeding is demonstrated in this paper to establish improvement in impedance values more clearly. The impedance at any vertex of a hexagonal patch is too high when compared to the characteristic impedance of the probe. Three vertex-fed hexagonal antennas are developed to demonstrate the effect of ground plane reduction within C-Band. The proposed technique can be optimized to match the impedance and achieve good return loss where monopole radiation characteristics are not an issue. A vertex-fed reduced ground hexagonal antenna is proposed here that operates around 5 GHz with a frequency span of 600 MHz. Thus, the proposed antenna is quite suitable for indoor wireless LAN (UNII-1) applications.

Supercapacitors or electrochemical capacitors are receiving greater interest because of their high-power density, long life, and low maintenance. We have synthesized CuS nanoparticles and graphene oxide (CuS–GO) nanocomposites for supercapacitor applications because of their low cost and excellent electrochemical properties. The phase purity of each material was determined using powder XRD studies. The bandgap was determined by UV-visible spectrophotometric studies. Scanning electron microscope and transmission electron microscope images revealed the nano-scale morphology of the synthesized particles. All the electrochemical measurements were conducted in a standard three-electrode configuration, using a platinum wire as the counter electrode and Hg/HgO as the reference electrode. CuS and its composites with graphene oxide on nickel foam were used as working electrodes. All the electrochemical measurements were performed in 3M KOH solution. The CuS–GO nanocomposite electrode showed a specific capacitance of 250 F/g, 225 F/g, 182 F/g, 166 F/g, 161 F/g, and 158 F/g at a current density of 0.5 A/g, 1 A/g, 5 A/g, 10 A/g, 15 A/g, and 20 A/g, respectively. CuS–GO electrodes showed a specific capacitance retention of 70% after 5000 charge–discharge cycles at a current density of 5 A/g.

Impact of co-doping (Gd and Mn) on the magnetic properties has been systematically investigated in SmCrO3 compound. For the synthesized compound Sm0.9Gd0.1Cr0.85Mn0.15O3 (SGCMO), below the Neel transition temperature and under low applied magnetic field, temperature induced magnetization reversal at 105 K (crossover temperature) was noticed in the field cooled magnetization curve. Magnetization reversal attained maximum value of -1.03 emu/g at 17 K where spin reorientation occurred. The magnetization reversal disappeared under higher applied field. From the M-H plots an enhancement in the magnetization was observed due to Gd doping. Magnetocaloric effect at low temperatures measured through the magnetic entropy change was found sixteen times higher for this compound as compared to pristine SmCrO3 and twice to that of SmCr0.85Mn0.15O3 compound. The study reveals the importance of co-doping in tailoring the magnetic properties of rare-earth chromites.