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The area of polluted water expands day by day due to the rapid increase in agricultural activities. Application and the excessive amount of fertilizer in the agricultural activity can reduce the water quality. One of the alternative way to remove pollutants from polluted water is phytoremediation technique. This paper attempt to evaluate the potential of Azolla pinnata act as a phytoremediation to treat the agricultural water. Three types of media with different dosage which are tap water, water added with organic fertilizer (chicken manure: dosage range of 10-30 g), and water added with inorganic fertilizer (growing fertilizer: dosage range of 10-30 g) were employed. Media B10 (water added with 10 g organic fertilizer) had the highest removal efficiencies for NH3-N, PO3-4, and NO-3 with 25%, 38.5% and 30%. In addition, turbidity and pH value diminished to 15.65% and 18.6%, respectively. However, it indicated that Azolla pinnata has the potential as an agent of phytoremediation especially for water polluted with organic fertilizers. [ABSTRACT FROM AUTHOR]

Nigella sativa oil [NSO] was enriched with biosynthesized silver nanoparticles [NP] by simple, cost-effective, and less time-consuming "Green Chemistry" protocol. This combination [NSO/NP], on blending with PVA, produced transparent and foldable hydrogel film. The structure, morphology, hydrophilicity and thermal stability of hydrogel film confirmed the incorporation of inorganic NP in organic PVA matrix. FTIR spectrum of nanocomposite film revealed good interactions between PVA matrix, NP and NSO. SEM of PVA and NSO combination film exhibited lipidic NSO cloud-like phase (light grey) dispersed in PVA matrix (dark contrast), while in nanocomposite hydrogel film these lipidic clouds disappeared completely, and PVA matrix appeared donning a grey sheath. The nanocomposite film showed good folding endurance (> 300 folds) and antimicrobial behavior against Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATTC 29212), Escherichia coli (ATCC 26922), Pseudomonas aeruginosa (ATCC 27853), Proteus mirabilis (ATCC 29906), Klebsiella pneumonia (MTCC109), Acinetobacter baumannii (NCTC 12156), and Candida albicans (ATCC90028) with prospective applications in antimicrobial packaging and wound dressings. [ABSTRACT FROM AUTHOR]

It is important to check the economic losses due to spontaneous metallic corrosion of major infrastructures, precious equipment's, and ensure the sustainable growth. Fabrication of environmentally benign functional polymeric material by transforming agricultural waste and products into value added polymeric products is of great importance in recent times. Here, we report the formulation of functional hybrid polymeric material using corn oil (CO) as our starting material. The functionality of CO was improved by green route, to produce corn diol fatty amide (HECA). Functionalization of CO was achieved in systematic manner by following green chemistry approach. First, diol fatty amide (HECA) was prepared followed by conversion of terminal OH groups of HECA into acrylic ester using condensation reaction with acrylic acid (AA). The base polymeric moiety was further modified to include phenyl acetylene functionality and SiO2 nanoparticle entities. The formulation of hydrophobic stable polymeric structure is important to sustain highly corrosive environment and long‐lasting performance of the material. The inclusion of different functionality and hydrophobic groups were confirmed by Fourier‐transform infrared and proton nuclear magnetic resonance spectroscopies. The baked coating was finalized by addition of phenol formaldehyde polymeric resin in different phr (part per hundred part of resin). The transmission electron microscopy, scanning electron microscope, energy dispersive X‐ray spectroscopy, and elemental mapping of the coating material confirms the formation of a hybrid material with uniform distribution of inorganic and organic components. The potentiodynamic polarization and electrochemical impedance spectroscopic analysis verified the better resistive performance of inorganic hybrid over the counter organic coatings. The enhanced thermal stability, hydrophobic character, and corrosion resistance performance of CO based coating material indicates the potential of the synthesized green route materials. [ABSTRACT FROM AUTHOR]

Manganese-substituted cerium oxide nanoparticles (CeO2:Mn NPs) were successfully prepared by the polyol-based co-precipitation method, and applied for construction of an electrocatalytic electrode. The crystallographic structure, phase purity, and morphological characteristics were examined by X-ray diffraction (XRD) and transmission electron microscopy (TEM) procedures. XRD results indicate a cube shape with an average crystalline size of ~ 10 nm. EDX analysis verified the homogeneous mixing of substitution of Mn ion in CeO2 crystal lattice. UV/visible spectrum and bandgap energy (3.27 eV) were observed to confirm the phase formation and optical properties of the material. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) tools were applied to inspect the electrochemical properties of the material. Both applied electrochemical methods verified the excellent electroactive surface area and electrocatalytic behavior of the constructed CeO2:Mn/glassy carbon electrode (GCE). The high sensitivity, strong reproducibility, and promising stability were also observed by the electrode on changing the potential scan rate. More significantly, in the catalyze or detection of the target analyte (urea), adequate recoveries were obtained for the evolved electrocatalyst/sensor, which showed a wide prospect of practical use. The high electrocatalytic activity of the CeO2:Mn/GCE model in the concentration range (3.90–1000 mg/dl) catalysts was the synergistic relationship between Mn and CeO2 NPs. This CeO2:Mn matrix could be an effective strategy to electro-catalyze various hazardous analytes (chemicals) such as catechol, phenol, and industrial effluents. [ABSTRACT FROM AUTHOR]

In this study, we developed an electrochemical sensor for sensitive detection of 4-NP in solution by using polyol-assisted co-precipitation process prepared copper doped cerium oxide nanoparticles (CeO2:Cu NPs). Phase purity, crystal structure, and morphology of the as-prepared nanoproduct were examined by X-ray diffraction and transmission electron microscopy images. Chemical composition was determined by energy dispersive x-ray analysis(EDX). UV/Visible spectrum was measured to determine the optical absorption properties and bandgap energies of the material. The prepared CeO2:Cu NPs were pasted on a glassy carbon electrode(GCE) to measure the electro-catalytic performance and further examining their sensing application through determining the 4-nitrophenol (4-NP) concentrations. The performance of the constructed electrode was assessed by cyclic voltammetry(CV) and electrochemical impedance spectroscopic(EIS) methods. The Cu doped CeO2 NPs exhibited demonstrated excellent electrochemical performance in the presence of 4-NPs in a 10 pH phosphate buffer solution (PBS). The voltammetry-acquired kinetic evidence shows that 4NP electro-oxidation is a strictly diffusion-controlled process and that four electrons are involved in the reaction mechanism. The constructed CeO2:Cu/GCE illustrated a high linearity range from 7.18-5000µL, a good detection limit (7.18 µL), with high sensitivity 1.4 μA mmol−1 L. The reproducibility of the fabricated electrode was also monitored through nine consecutive CV cycles to measure their stability. [ABSTRACT FROM AUTHOR]

Chemically synthesized cobalt-doped cerium oxide nanoparticles (CeO2: Co NPs) were successfully prepared by complexed based co-precipitation process. The structural, morphological, chemical composition, optical properties, and electrocatalytic properties were determined by X-ray diffraction pattern (XRD), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), UV/visible absorption spectroscopy, and cyclic voltammetry techniques. Owing to the wide-spread applications of CeO2 NPs in various fields of applied material sciences, transition metal ion-doped CeO2: Co NPs exhibited excellent electrocatalytic properties. Outstanding physiochemical properties of CeO2, such as reversible oxidation states, high ionic mobility, large oxygen storage ability, effective large specific surface area, and the excellent current response, were observed in the electrocatalytic oxidation of hydrazine. The presence of transition metal ions (cobalt) improves the oxidation potential of hydrazine. Cyclic voltammetry was analog with the electrochemical impedance spectroscopy results, which revealed the enhanced with rapid sensing response against hydrazine. The electrocatalytic results of the CeO2: Co NPs electrode exhibited excellent voltammetry and impedance spectroscopy performance towards the hydrazine oxidation. The fabricated chemical sensor shows a wide linear detection range from 7.18 to 1000 µM, a low detection limit 7.2 µM, and sensitivity of 2.42 µAmLµM−1 cm−2. The fabricated sensing electrode demonstrated long-term steadiness, resulting in high sensitivity, selectivity, repeatability/reproducibility, and rapid detection of hydrazine. [ABSTRACT FROM AUTHOR]

Diabetes and its related complications are responsible for severe morbidity and deaths round the globe. Diabetic foot infections (DFIs) are severe and dreadful complication of diabetes mellitus. DFI/DFUs are colonized with numerous pathogenic, multi-drug-resistant microorganisms and progression in colonization of these microorganism leads to biofilm establishment making treatment challenging. There is an indispensable requirement for alternative approaches to combat this threat. In the present assignment, titanium oxide nanoparticles (TiO2-NPs) were fabricated from the leaf extract of Ochradenus arabicus and inhibition of biofilm and related functions was examined against multi-drug-resistant strains of P. aeruginosa and methicillin-resistant S. aureus (MRSA) isolated from foot ulcers. Bio-fabricated TiO2-NPs reduced biofilm formation in the selected strains by 22–70% at tested sub-MICs. Significant reduction in alginate and severely impaired motility of P. aeruginosa strains was also observed. Key functions such as cell surface hydrophobicity and EPS production that contribute in the attachment and maintenance of biofilm, respectively, were also inhibited considerably in test strains at sub-MICs. Statistically significant reduction (51–63%) in the preformed biofilms of all strains was also recorded. Interaction of bacterial cell and TiO2-NPs resulted in increased levels of ROS, and this could be the plausible the reason for the biofilm inhibitory action of NPs. These NPs could be exploited in the current treatment strategies to combat the threat of biofilm-based drug-resistant diabetic foot infections and facilitate wound healing. [ABSTRACT FROM AUTHOR]

The PdS/p-Si heterojunction was fabricated by preparation of PdS thin films on the p-type Si (10 0) substrates using versatile SILAR method. The alteration of nanostructural, morphological, optical and I–V characterization of CuxPd1−xS/p-Si (x = 0–0.1) heterojunction was examined at the different Cu-doping level to inspect the doping effects on the properties of heterojunction. The X-ray diffraction investigated that the crystallinity of prepared thin films enhanced as a function of Cu concentration. The morphological analysis presented that the PdS thin films was smooth, homogeneous and closed packed spherical grains. Electron dispersive X-ray (EDX) analysis confirmed the stoichiometric composition of PdS thin films. The diffuse reflectance spectroscopy in the prepared PbS/p-Si heterojunction was reduced and the band edge showed the blue shift in the visible range. Photoluminescence (PL) spectra revealed that the PbS/p-Si heterojunction recombination rate is decreased with Cu-doping. The effects of Cu-doping level on the electrical parameters of heterojunction such as ideality factor (n), saturation current (IS), barrier height (Φb) and series resistance (Rs) were computed by the execution of current–voltage (I–V) properties. Electrical properties indicated that behavior of the PdS/p-Si heterojunction were precisely controlled by doping level. [ABSTRACT FROM AUTHOR]

The environmental problem is a big issue in the current scenario because the human beings are affected via natural or manmade sources. Over a range of industrial pollutents, the nitrophenol (referred to as 4-NP) known as harmful industrial chemical for the environment and listed as a carcinogenic compound for human health. To keep this view the present manuscript describes the formation of highly crystalline silicon nanoparticles (Si-NPs) and applied for the electrochemical sensing of 4-NP. The Si-NPs exhibit numerous applications in various directions such as catalyst, solar cells, LEDs, batteries etc. The Si-NPs were formed from the physical approach with using argon-silane mixture in a gas chamber with impregnation of microwave plasma. The processed material was examined through various techniques such as X-ray diffraction pattern (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Fourier transform spectroscopy (FTIR). It reveals from the acquired analysis that the size of each NP is ~ 4 nm with good structural and chemical characteristics and applied as a film form against to check the sensing of 4-NP with three electrode system. The electrochemical studies were conducted through cyclic voltammetry (CV) in terms of their low to high concentration (7.8, 15.62, 31. 25, 62.25, 250, 500, 1000 μM in PBS), scan rate at variable potential was accessed from 5 to 100 mV with Si-NPs based electrode. The sustainability, reproducibility and efficacy of the formed sensor (Si-NPs/GCE) was examined in occurrence with 4-NP (62.25 μM) for seven consecutive cycles. Including to this, chronoamperometry (0 to 1500 s) and electrochemical impedance spectra (7.8–1000 μM in PBS) were also analyzed. On the basis of acquired results and discussion a probable mechanism was also described. [ABSTRACT FROM AUTHOR]

In the present study, Ag2O–Al2O3–ZrO2 based trimetallic oxide nanocatalyst was designed using simple microwave assisted reduction method. It was characterized using various techniques such as Fourier transform-infrared (FT-IR), X-ray diffractometer (XRD), electron microscopy [scanning electron microscope (SEM), transmission electron microscope (TEM)] and X-ray photoelectron spectroscope (XPS). It was utilized for the degradation of nicosulfuron herbicide and the influence of microwave (MW) and UV radiations on the degradation rate was also studied. Maximum of 78% degradation was obtained within 50 min. Scavenging studies showed the major involvement of ·OH and ·O2− radicals in the degradation process. Possible heterostructures (traditional and Z-scheme) with their possible charge transfer were also studied. Nyquist plots and photoluminescence (PL) analysis showed the high charge transfer and lowered recombination in Ag2O–Al2O3–ZrO2. Possible degradation mechanism was also developed using LC–MS. Reusability studies were carried out for consecutive 5 cycles and results indicated the appreciable photocatalytic ability after every repeated cycles. [ABSTRACT FROM AUTHOR]

In this study, an electrochemical sensor for the detection of 4-Nitrophenol (referred to as 4-NP) was developed based on templated silver nanoparticles (AgNPs) on reduced graphene oxide (rGO) nanosheets (Ag-rGO) and utilized as an electrocatalyst. It was found that the resulting composite exhibits enhanced catalytic activity towards the reduction of 4-NP. The cubic shaped AgNPs templated on rGO nanosheets has been successfully fabricated by a chemical reduction method using sodium borohydride (NaBH4), and it was well characterized through morphological and electrochemical techniques: Ultraviolet–Visible spectroscopy (UV -Vis), scanning electron microscopy (SEM) equipped with energy-dispersive spectroscopy (SEM–EDS), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), cyclic voltammetry (CV), and chronoamperometry. The obtained results revealed that the AgNPs scattered on rGO sheets are spherical in shape, and it's estimated to be a dimension of ~ 60 nm in size. The prepared crystalline Ag-rGO nano sheets were further applied as an electrode material for the electrochemical examination with three electrode system to sense the hazardous material 4-NP in PBS. The electrochemical studies were conducted through CV under the condition of bare and coated electrode (Ag-rGO/GCE) with influence of concentration (4-NP from 2 to 150 mM), scan rate, reproducibility (RSD-2.87%) and stability test (4-NP-20 µM) were examined. The data reveal that the Ag-rGO/GCE exhibit highly reproducible and sustainable for the reduction of toxic 4-NP. The chronoamperometry study for current and time response was also studied at two different potentials (− 0.3 V & − 0.6 V), respectively. [ABSTRACT FROM AUTHOR]

A series of cubic porous perovskites with the general formula BaFe 1−x Ni x O 3 have been prepared via the sol-gel-citrate route and investigated as a catalyst for the aerobic oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) using molecular O 2 as the oxidant under ambient pressure. Doping and the synergetic interaction between Ni and Fe ions in the BaFeO 3 perovskites significantly affected the conversion, product selectivity, specific activity, turnover number, and turnover frequency. A BzH selectivity of >99.9% was achieved in the oxidation of BzOH. Among the prepared perovskites, BaFe 0.4 Ni 0.6 O 3 showed the highest catalytic conversion and specific activity under the optimized reaction conditions. Based on the catalytic performance, further studies on the recyclability, and influences of temperature and catalyst loading were carried out using this catalyst. The catalyst recyclability test showed a negligible loss in activity after five consecutive cycles. [ABSTRACT FROM AUTHOR]

Poly (urethane-glutaric-esteramide) (PUGEA) was synthesized using corn oil and glutaric acid and further treated with toluene-2, 4-diisocyanate. Fumed silica with 1, 2, and 3 weight percentage was included in the synthesized PUGEA resin to obtain PUGEA-1, PUGEA-2 and PUGEA-3 nanocomposite resins, respectively. The chemical structure of glutaric polyesteramide and PUGEA was characterized by Fourier-transform infrared spectroscopy and nuclear magnetic resonance (1H and 13C NMR). The morphology, hydrophobicity and thermal stability of the PUGEA nanocomposites were investigated by using scanning electron microscopy and energy-dispersive X-ray spectroscopy, by measuring contact angle and by thermogravimetric analysis (TGA). Afterward, the PUGEA/fumed silica nanocomposite coatings were applied on mild steel and dried at room temperature, and they were physico-mechanically characterized by measuring their scratch and pencil hardness, bending, impact resistance and cross-hatch adhesion. The anti-corrosion effectiveness of PUGEA-2 was investigated by electrochemical impedance spectroscopy immersing it for 42 days in a 3.5 wt% NaCl aqueous solution. Finally, TGA reveals that the PUGEA-3 nanocomposite coating can be safely used up to 275 °C. [ABSTRACT FROM AUTHOR]