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We report on the sensing of a hazardous pesticide alphacypermethrin (ACM) using electrochemical technique through a nanocomposite film modified electrode. The nanocomposite film comprising of octadecylamine, chitosan, polyvinyl alcohol-silver nanowires and haemoglobin, shortly (OCPAH), was prepared by Langmuir–Blodgett (LB) film deposition technique on various substrates and electrodes. The composite LB film was characterised by UV-visible spectroscopy and scanning electron microscopy, which confirms the stable and multilayer film. The LB film modified electrode was used for sensing ACM pesticide by cyclic voltammetry (CV), differential pulse voltammetry (DPV), and square wave voltammetry (SWV) techniques. The achieved sensing parameters such as limit of detection as 14 nM, 5 nM and 10 nM; linear range as 10–100 nM, 10–40 nM and 50–100 nM/10–100 nM; and sensitivity as 0.418 µA/nM/cm2, 0.259 µA/nM/cm2 and 0.271 µA/nM/cm2 for CV, DPV and SWV techniques, respectively. The reported sensor is found to have stability of 74% upto 20 cycles, the relative standard deviation (RSD) value for metal ion/organic interference species as 2% and for real samples are within 1.4% using CV technique. The reported nanocomposite-based ACM pesticide sensor will open up new options for research on LB film nanocomposite-based sensing of different organophosphorus groups of pesticides. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Clinicians in tuberculosis and dengue endemic regions should have heightened vigilance for drug‐induced liver injury (DILI) overlapping with active infections, enabling prompt recognition and life‐saving conservative management. Severe dengue and drug‐induced liver injury (DILI) are significant independent risk factors for acute liver failure. The co‐occurrence of these conditions significantly complicates clinical management. Here, we describe the case of a 21‐year‐old Nepali female who developed acute liver failure during antitubercular therapy (ATT). The patient, presenting with fever and nausea after 3 weeks of ATT, subsequently received a diagnosis of severe dengue. Laboratory evidence indicated markedly elevated transaminases (AST 4335 U/L, ALT 1958 U/L), total bilirubin (72 μmol/L), and INR (>5). Prompt discontinuation of first‐line ATT, initiation of a modified ATT regimen, and N‐acetylcysteine (NAC) infusion facilitated the patient's recovery after a week of intensive care. This case underscores the potential for synergistic hepatotoxicity in regions where multiple endemic illnesses coincide. Early recognition of DILI, cessation of offending agents, and comprehensive intensive care are crucial interventions. While the definitive efficacy of NAC remains under investigation, its timely administration in these complex cases warrants exploration for its potential lifesaving benefits. [ABSTRACT FROM AUTHOR]

Nickel-based coatings deposited by high-velocity flame spray (HVFS) process have been widely used to overcome the slurry erosion in a hydro turbine, where many turbine components are subjected to severe erosion failure. In this work, new kind of multi-dimensional Ni-40TiO2 and Ni-20TiO2-20Al2O3 coatings consisting of nanostructured and micron-sized particles of TiO2 and Al2O3 were developed by HVFS process on CA6NM(13Cr4Ni) turbine steel. The in-depth characterization of the synthesized nanostructured powders, prepared coating compositions and the deposited coating was done through dynamic light scattering, scanning electron microscopy, energy-dispersive spectroscopy and x-ray diffraction techniques. The mechanical and microstructural properties of the as-sprayed specimens were evaluated and discussed in this paper. The results showed that the multi-dimensional Ni-40TiO2 coating possessed lower porosity (0.8-2.0%), higher avg. microhardness (605 ± 37 HV0.1), and better bond strength (66.4 MPa) than the Ni-20TiO2-20Al2O3 coating. [ABSTRACT FROM AUTHOR]

Hydro turbine components are subjected to severe erosion especially during the rainy season in the Himalayan region. To protect the CA6NM turbine steel, an attempt has been made to develop the Ni-40Al2O3 composite coating using a high-velocity flame spray process. To lower the porosity, the coating was developed by mixing two different sizes (viz. micron and nano) of alumina (Al2O3) reinforcement with 60 wt.% Ni as the base powder. The characterization of the as-sprayed coating was done by scanning electron microscopy/energy dispersive X-ray spectroscopy, and PANalytical X-ray diffraction technique, whereas mechanical characterization was done for the evaluation of microhardness, bond strength, and surface roughness. The performance of the developed coating was compared with uncoated steel on slurry jet erosion test rig under accelerated conditions by varying the three parameters, viz. slurry concentration, erodent size, and impact velocity. Ni-40Al2O3 coating was found to be effective for minimizing the erosion rate in comparison with the uncoated steel. Scanning electron microscopy of eroded coatings mainly reveals the brittle type of signature on the coating. [ABSTRACT FROM AUTHOR]

Various aspects such as development, experimentation, and analysis have been covered in the present work to examine the behavior of test coatings under slurry erosion. The primary objective of the present study was to establish the specific mass loss from the test coatings under various slurry environmental conditions and highlights the importance of the addition of alumina in improving the slurry erosion resistance of Ni-TiO2 coating. To attain this objective, two powder compositions, viz. Ni-20TiO2 and Ni-15TiO2-5Al2O3 were deposited onto the CA6NM grade hydro-turbine steel using high velocity frame spray process. The microstructural characterization of the coatings was done by employing surface roughness tester, scanning electron microscope/energy-dispersive X-ray spectroscopy, and X-ray diffraction techniques, whereas mechanical analysis was carried out using micro-hardness and bond strength tester. The slurry erosion tests were performed using an indigenously fabricated high speed slurry erosion test rig at different levels of rotational speed, average particle size of erodent, and slurry concentration in order to explore their effects on slurry erosion performance of test coatings. The slurry erosion results, as well as scanning electron microscope observations of eroded specimens, revealed higher slurry erosion resistance of Ni-15TiO2-5Al2O3 coating in comparison with Ni-20TiO2 coating. Furthermore, each operational parameter was found to have a proportional effect on specific mass loss in case of both the coatings. [ABSTRACT FROM AUTHOR]

Purpose This paper aims to cover all the aspects of development, investigation and analysis phases to evaluate the slurry erosion performance of test coatings. The powders having composition of Ni-20Al2O3 and Ni-15Al2O3-5TiO2 were deposited on CA6NM grade turbine steel by using high velocity flame spray (HVFS) technique. The characterization of the coatings was done with the help of SEM/EDS and XRD techniques. Various properties such as micro-hardness and bonding strength of the coatings were also evaluated. Thereafter, these coatings were subjected to an indigenously developed high speed slurry erosion tester at different levels of rotational speed, erodent particle size and slurry concentration. The effect of these parameters on the erosion behavior of coatings was also evaluated. The slurry erosion tests and SEM of the eroded surfaces revealed remarkable improvement in slurry erosion resistance of Ni-15Al2O3-5TiO2 coating in comparison with Ni-20Al2O3 coating.Design/methodology/approach Two different compositions of HVFS coating were developed onto CA6NM steel. Subsequently, these coatings were evaluated by means of mechanical and microstructural characterization. Further, slurry erosion testing was done to analyze the erosive wear behavior of developed coatings.Findings The coatings were successfully developed by HVFS process. Cross-sectional microscopic analysis of sprayed coatings revealed a continuous and defect-free contact between substrate and coating. Ni-15Al2O3-5TiO2 coating showed higher value of bond strength in comparison with Ni-20Al2O3 coating. Under all the testing conditions, Ni-15Al2O3-5TiO2 coatings showed higher resistance to slurry erosion in comparison with Ni-20Al2O3 coatings. Rotational speed, average particle size of erodent and slurry concentration were found to have proportional effect on specific mass loss of coatings. The mixed behavior (brittle as well as ductile) of the material removal mechanism was observed for the coatings.Originality/value From the literature review, it was found that researchers have documented the various studies on Ni-Al2O3, Ni-TiO2 and Al2O3-TiO2 coatings. No one has ascertained the synergetic effect of Alumina and Titania on the slurry erosion performance of Nickel-based coating. In view of this, the authors have developed Ni-Al2O3 and Ni-Al2O3-TiO2 coatings, and an attempt has been made to compare their mechanical, microstructural and slurry erosion characteristics. [ABSTRACT FROM AUTHOR]

Degradation of the hydroturbine components due to slurry erosion is a serious issue, especially for the hydropower plants situated on the rivers originating from Himalayas in India. In the current investigation, slurry erosion performance of two stainless steels (CA6NM and CF8M), which are commonly used in hydroturbine power plants, has been studied. A high-speed erosion test apparatus was used for the studies. Slurry collected from an actual hydropower plant was used as the abrasive media in the test apparatus. The effect of slurry concentration (ppm), average particle size of slurry particles and rotational speed on the slurry erosion behaviour was investigated under different experimental conditions. The analysis of eroded samples was done using scanning electron microscopy (SEM) and stylus profilometry. SEM images showed signatures of formation of lips, ploughing, crater and microcutting on eroded surface of steels. [ABSTRACT FROM AUTHOR]

The presence of silt sediments in the flowing river is the primary reason for the severe failure of hydro-power turbine components. This study insights the effect of erosion parameters on the performance of two multi-dimensional novel compositions (namely Ni-40TiO2 and Ni-20TiO2-20Al2O3) developed on the CA6NM turbine steel by high velocity flame spray (HVFS) method. The Ni-40TiO2 coating with lower porosity, higher fracture toughness, and microhardness, showed the highest slurry erosion resistance than the other counterparts. This outstanding performance is attributed to the uniform distribution of the multi-dimensional TiO2 grains in the coating, which effectively reduces the material loss rate during slurry erosion. The Ni-40TiO2 coating indicated a mixed mechanism of material removal, while the brittle mechanism was observed in the case of Ni-20TiO2-20Al2O3 coating. A model has been proposed to estimate the erosion rate of these proposed coatings. [ABSTRACT FROM AUTHOR]

Bifenthrin (BF), a widely used pyrethroid pesticide in farming, lacks highly sensitive and selective sensors despite its extensive application. Ruthenium complexes are very effective for selective sensing applications but suffer from structural instability at elevated conditions, electrochemical activity, and the use of costly electrolytes. This work improves their electrochemical activity and mechanical strength by incorporating silver nanowires and replacing the costly electrolyte with abundant KCl + PBS, resulting in enhanced signal performance. Herein, a ruthenium complex containing composite film was immobilized on a platinum (Pt) electrode using Langmuir Blodgett technique. The fabricated sensor has been characterized by differential pulse voltammetry (DPV) based electrochemical technique. The BF pesticide sensing parameters, including the limit of detection (LOD), linear range (LR), and sensitivity, were evaluated using SWV, DPV, and CV techniques. Among these, the DPV technique demonstrated the best performance, achieving a sensitivity of 0.648 μA cm -2 μM -1 , a LR of 1-10 μM, and a LOD of 1 μM. The relative standard deviation (RSD) values using DPV are found to be 6.3% (repeatability study), 3% (reproducibility study), 8% (metal ion interference), 5% (organic species interference), and 2% (real sample study), which are much lesser than the World Health Organization (WHO) recommendation of RSD value on the pesticide ( i.e. 20%). The BF sensor demonstrated a selectivity of 2× difference of peak height response compared to similar pesticides. The reported pesticide sensor will open new options for sensor research using metal complex-based LB film nanocomposite., Competing Interests: The authors declare that there is no competing interest., (This journal is © The Royal Society of Chemistry.)