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In this work, the Metal Inert Gas (MIG) welding process is used for depositing the Inconel 718 over the base substrate of Stainless steel 321. The optimal welding conditions like 50% overlap, Direct Current (DC) plus mode with a pulse on time (1–5 s), frequency (0.25–1 Hz), peak current (120 A), base currents (60% of peak current), and speed (150–350 mm/min) are used for the successful hard-facing. The quality of the hard-facing is analyzed by conducting microstructural studies, tensile tests, microhardness, wear behavior, and electrochemical studies. Post-processing for wear and electrochemical studies is done by Scanning Electron Microscope SEM–EDX analysis. Microstructural studies revealed the presence of columnar dendrites and equiaxed at the top of the hard-faced layer. Hard-faced layer depicts the highest ultimate tensile strength of 772 N/mm2 with an elongation of 31.50% due to the support of Nickel components. The presence of the voids and dimples is identified from the SEM fractography. The maximum hardness value of 212 HV 0. 5 is measured at the top of the hard face layer. The microhardness of the hard-faced layer increased by 17.77% higher than its base substrate. Because of the hard precipitates and higher microhardness made by the weld thermal cycle, the hard-face layer showed maximum Co-efficient of Friction (CoF) of 0.540. Debris and grooves are found with the SEM examination of the wear specimens. Higher impedance offers better corrosion resistance to the hard-faced layer Inconel 718. The EDX analysis confirms the presence of Chromium, Molybdenum, and Niobium contents at the hard-faced layer. These elements silently support better corrosion resistance compared to the base substrate of Stainless steel 321. [ABSTRACT FROM AUTHOR]

In this study, a Ru-doped Ni pellet-type catalyst was prepared to produce hydrogen via steam methane reforming (SMR). A small amount of Ru addition on the Ni catalyst improved Ni dispersion, thus affording a higher catalytic activity than that of the Ni catalyst. During the daily startup and shutdown (DSS) operations, the CH4 conversion of Ni catalysts significantly decreased because of Ni metal oxidation to NiAl2O4, which is not reduced completely at 700 °C. Conversely, the oxidized Ni species in the Ru–Ni catalyst can be reduced under SMR conditions because of H2 spillover from the surface of Ru onto the surface of Ni. Consequently, the addition of a small quantity of Ru to the Ni catalyst can improve the catalytic activity and stability during the DSS operation. [ABSTRACT FROM AUTHOR]

The effects of the SnO2 pore size and metal oxide promoters on the sensing properties of SnO2-based thick film gas sensors were investigated to improve the detection of very low H2S concentrations (

The sensing behavior of SnO2-based thick film gas sensors in a flow system in the presence of a very low concentration (ppb level) of chemical agent simulants such as acetonitrile, dipropylene glycol methyl ether (DPGME), dimethyl methylphosphonate (DMMP), and dichloromethane (DCM) was investigated. Commercial SnO2 [SnO2(C)] and nano-SnO2 prepared by the precipitation method [SnO2(P)] were used to prepare the SnO2 sensor in this study. In the case of DCM and acetonitrile, the SnO2(P) sensor showed higher sensor response as compared with the SnO2(C) sensors. In the case of DMMP and DPGME, however, the SnO2(C) sensor showed higher responses than those of the SnO2(P) sensors. In particular, the response of the SnO2(P) sensor increased as the calcination temperature increased from 400 °C to 800 °C. These results can be explained by the fact that the response of the SnO2-based gas sensor depends on the textural properties of tin oxide and the molecular size of the chemical agent simulant in the detection of the simulant gases (0.1–0.5 ppm).

Field effect transistor (FET)‐based nanoelectronic biosensor devices provide a viable route for specific and sensitive detection of cancer biomarkers, which can be used for early stage cancer detection, monitoring the progress of the disease, and evaluating the effectiveness of therapies. On the road to implementation of FET‐based devices in cancer diagnostics, several key issues need to be addressed: sensitivity, selectivity, operational conditions, anti‐interference, reusability, reproducibility, disposability, large‐scale production, and economic viability. To address these well‐known issues, significant research efforts have been made recently. An overview of these efforts is provided here, highlighting the approaches and strategies presently engaged at each developmental stage, from the design and fabrication of devices to performance evaluation and data analysis. Specifically, this review discusses the multistep fabrication of FETs, choice of bioreceptors for relevant biomarkers, operational conditions, measurement configuration, and outlines strategies to improve the sensing performance and reach the level required for clinical applications. Finally, this review outlines the expected progress to the future generation of FET‐based diagnostic devices and discusses their potential for detection of cancer biomarkers as well as biomarkers of other noncommunicable and communicable diseases. [ABSTRACT FROM AUTHOR]

C1‐selective deuteration of aromatic aldehydes is of great importance for isotopic labeling and for improving the characteristics of drug molecules. Due to the recent increase in the use of deuterated pharmacological drugs, there is a pressing need for synthetic procedures that are efficient to produce deuterated aromatic aldehyde analouges. Deuterium labeling approaches are typically used as an effective tool for researching pharmaceutical absorption, distribution, metabolism, and excretion (ADME). Furthermore, deuterium‐labeled pharmaceuticals are intended to increase therapeutic effectiveness and reduce side effects by extending the half‐life of drug response. In the last few years, several catalytic or non‐catalytic methods have been developed to synthesize deuterated aromatic aldehydes. In this concern, we offer a brief overview of the various synthetic strategies and practical methods for the formyl‐selective deuterium labeling of aromatic aldehydes using different deuterium sources. [ABSTRACT FROM AUTHOR]

A covalently functionalized-multiwalled carbon nanotubes (f-MWCNTs) with 2-aminothiophenol (2ATP) supported cerium oxide nanoparticles (CeO2 NPs) adsorbed on selenium nanoparticles (Se NPs) (MWCNT(SH)/CeO2@Se NPs) was prepared using a simple chemical route and utilized for the inactivation of Gram-positive/negative bacteria and fungus. In this investigation, a mixture of cerium nitrate and selenium dioxide precursor salts in the presence of MWCNT(SH) in p-toluene sulfonic acid medium (0.5 M) was reduced with sodium hydroxide by hydrothermal method, and the pH was maintained at 4.5. The uniform dispersion and stability of CeO2@Se NPs are strongly influenced by the thiol group (–SH) present in MWCNT(SH) supporting matrix. Morphology and microstructure analysis revealed good dispersion of CeO2@Se NPs onto MWCNT(SH) support matrix. The FTIR and UV–Visible spectroscopy results clearly revealed that the CeO2@SeNPs were anchored on MWCNT(SH) matrix. The antimicrobial studies were performed against a set of microbes, and they showed that Gram-negative (G −) stains were relatively more susceptible to CeO2@Se NPs-loaded MWCNT(SH) than Gram-positive (G +) stains. MWCNT(SH)/CeO2@Se NPs exhibited comparatively better microbicidal activity than MWCNT(SH). This is due to the influence of thiol (–SH) groups in stabilizing and protecting CeO2@Se NPs on MWCNT(SH) support against their leaching and agglomeration processes and thus augments the microbicidal effect of MWCNT(SH)/CeO2@Se NPs. [ABSTRACT FROM AUTHOR]

A novel method for selective and sensitive detection of chloride ion plays a vital role in environmental monitoring, industrial and healthcare sectors. Here, we spotlight the synthesis, characterization and electrochemical performance analysis of electrospun PVA-PANi-g-C3N4 nanofibers (NFs) over screen printed carbon electrode and engaged as a modified NF electrode for chloride ion determination. The resulting nanofibers morphological views, functional groups and elemental composition were captured and recorded by FESEM, FTIR and XPS. The electrochemical behaviour of PVA-PANi-g-C3N4 NFs was studied by cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometric techniques, as the results directed that the modified NF electrode reveals a significant electrochemical sensitivity, selectivity for Cl− ion with the value of linear regression co-efficient R2 = 0.99. The lowest limit of detection 0.2 µM with greater sensitivity (1.6082 µM µA/cm2) was succeeded. Owing to its synergistic interaction amid the PVA-PANi with g-C3N4 NF combinations an efficient electron transfer pathway was achieved which leads to an excellent ionic diffusion. Further, the outcomes from the real sample analysis creating them attractive and helping in profound study for electrochemical sensor towards practical applications. [ABSTRACT FROM AUTHOR]

Summary: In this study, we report a novel biomass‐derived porous carbon nanostructures (BD‐PCNSs) obtained from Lantana camara stem (LAC) using a simple and low‐cost preparation method. LAC biomass was processed with a temperature‐controlled hydrothermal precarbonization cum pyrolysis technique and followed by alkaline surface activation to achieve BD‐PCNSs. The physicochemical properties for the obtained BD‐PCNSs material were confirmed using X‐ray diffraction, scanning electron microscopy, nitrogen sorption isotherms, and X‐ray photoelectron spectroscopy. As‐prepared BD‐PCNSs exhibited excellent performances toward supercapacitance and wastewater treatment. BD‐PCNSs showed high‐specific capacitance ~146 Fg−1 in the aqueous electrolyte with excellent coulombic efficiency, and cyclic retention affirms its green energy storage device fabrication. Also, maximum adsorption capacity (106.4 mg g−1) was achieved for the efficient removal of ibuprofen from wastewater and proven as a promising eco‐friendly, and low‐cost absorbent material claim its practical applications. [ABSTRACT FROM AUTHOR]

The cobalt selenide nanoparticles (CoSe NPs) were prepared by a simple hydrothermal method, and polyaniline nanofibers (PANI NFs) were prepared by a chemical oxidative polymerization and its composite NFs were prepared by incorporating CoSe onto PANI at the optimized wt% 1:1 by ultrasonication to use as a newer photocathode for dye‐sensitized solar cells (DSSCs). The physio‐chemical properties of the prepared CoSe NPs/PANI NFs composite NFs were investigated by field emission scanning electron microscope, X‐ray diffractometer, and Raman spectroscopy. The results revealed that the phase pure CoSe NPs were decorated onto the PANI NFs without affecting their physio‐chemical nature. The electrochemical characteristics of CoSe NPs/PANI NFs composite NFs as photocathode were investigated by electrochemical AC‐impedance, cyclic voltammetry, and Tafel polarization studies. The CoSe decorated PANI composite NFs displayed excellent electrocatalytic behavior toward the tri‐iodide reduction. Further, DSSC fabricated with CoSe/PANI composite NFs as the photocathode exhibited the highest photoconversion efficiency of 9.14% than that of the pristine CoSe NPs and PANI NFs‐based counter electrodes (CEs). This is attributed to the synergistic electrocatalytic ability of CoSe NPs and the multiple interfacial charge transferability of PANI NFs. These results suggest that CoSe decorated PANI composite NFs could be used as a promising CE to fabricate high‐performance DSSC. [ABSTRACT FROM AUTHOR]

Summary: In this study, we report a new phosphotungstic acid‐Titania embedded polyaniline (PANI/PTA/TiO2) nanocomposite modified hybrid electrode for efficient methanol electro‐oxidation reaction. The PANI/PTA/TiO2 nanocomposite was prepared via a simple in‐situ polymerization method. The fabricated modified electrode's surface morphology and elemental analysis were characterized using field‐emission scanning electron microscopy with energy‐dispersive X‐ray spectroscopy and mapping technique. The phase structure and molecular vibrational studies were identified using an X‐ray diffraction and Fourier‐transform infrared spectroscopic techniques. The electrochemical performance of the modified electrodes was studied using cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopic techniques. The PANI/PTA/TiO2 nanohybrid modified electrode displayed the superior electro‐catalytic activity towards methanol oxidation reaction at 0.2 V potential with the charge transfer resistance of 218 Ω, and showed excellent stability up to 1200s in an alkaline medium. The developed nanocomposite material can be used as a potential nanohybrid anode catalyst for the application of direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

Summary: In this study, a simple and facile electrochemical deposition technique was employed to fabricate fluorine‐doped tin oxide‐based polydiphenylamine‐polyaniline/phosphotungstic acid copolymer nanocomposite modified electrode (FTO/PDPA‐PANI/PTA) for high‐performance supercapacitors application. Crystalline and morphological structure and coating thickness of PDPA‐PANI/PTA nanocomposite on FTO were characterized using X‐ray diffraction, scanning electron microscope, and atomic force microscope. The fabricated nanohybrid electrode exhibits superior specific capacitance of 360 Fg−1 at 1 mA current density. The higher capacitive behavior and cyclic steadiness of FTO/PDPA‐PANI/PTA modified electrode were achieved because of the presence of tungsten in the PDPA/PANI co‐polymer nanonetworks provide efficient interaction which enhances the fast electron transfer progressions. Electrochemical impedance spectroscopic (EIS) studies ensure the capacitive behavior of the electrodeposited nanohybrid modified electrode with a characteristic EIS semicircle in the lower frequency region. Further, a superior specific capacitance with 82% excellent capacitance retention after 1000 cycles, recommends a practical application in supercapacitor device electrodes. [ABSTRACT FROM AUTHOR]

The effects of the SnO2 pore size and metal oxide promoters on the sensing properties of SnO2-based thick film gas sensors were investigated to improve the detection of very low H2S concentrations (<1 ppm). SnO2 sensors and SnO2-based thick-film gas sensors promoted with NiO, ZnO, MoO3, CuO or Fe2O3 were prepared, and their sensing properties were examined in a flow system. The SnO2 materials were prepared by calcining SnO2 at 600, 800, 1,000 and 1,200 °C to give materials identified as SnO2(600), SnO2(800), SnO2(1000), and SnO2(1200), respectively. The Sn(12)Mo5Ni3 sensor, which was prepared by physically mixing 5 wt% MoO3 (Mo5), 3 wt% NiO (Ni3) and SnO2(1200) with a large pore size of 312 nm, exhibited a high sensor response of approximately 75% for the detection of 1 ppm H2S at 350 °C with excellent recovery properties. Unlike the SnO2 sensors, its response was maintained during multiple cycles without deactivation. This was attributed to the promoter effect of MoO3. In particular, the Sn(12)Mo5Ni3 sensor developed in this study showed twice the response of the Sn(6)Mo5Ni3 sensor, which was prepared by SnO2(600) with the smaller pore size than SnO2(1200). The excellent sensor response and recovery properties of Sn(12)Mo5Ni3 are believed to be due to the combined promoter effects of MoO3 and NiO and the diffusion effect of H2S as a result of the large pore size of SnO2. [ABSTRACT FROM AUTHOR]