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991.
992.
The progress in the development of gas sensors has considerably grown using some novel nanomaterials of metal, metal oxide and composite. In the current study, we intended and evaluated the properties of nanomaterials like CeO2, NiO, and CeO2–NiO composite and its application as NO2 gas sensor. Sensing of low concentration of NO2 gas at optimum functional temperature was succeeded using CeO2–NiO nanocomposites (NCs) film. The working temperature ranges in between 100 and 225 ?°C. Highly crystalline nanomaterials (CeO2, NiO and CeO2–NiO) have been prepared by applying microwave-assisted sol-gel route. The as-prepared nanomaterials are characterized for their structure, size, morphology and constitution by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis. XRD studies of nanoparticles reveal the formation of nanoscale CeO2 and NiO with crystallite size 26, 23 ?nm, respectively. Both are having a face centered cubic structure. The nanocomposite (NC) Ce:Ni ?= ?60:40 has crystallite size of 13 ?nm. XRD study of NCs shows assimilation of Ni metal into the ceria and proves physical similarities of two phases. It can be observed from SEM that prepared NC has a porous surface which enables more surface active sites for adsorbing oxygen. The optical properties are measured with the help of UV–Vis. Spectroscopy. Optical band gaps of 3.19, 3.41 and 2.9 ?eV were observed for CeO2, NiO nanoparticles (NPs) and CeO2–NiO NC, respectively. Gas sensing properties state that the NC material shows a higher gas response % of 67.34% for NO2 gas (25 ?ppm) at comparatively low operating temperature (125 ?°C). It gives response time as (~28 ?s) and the recovery (~54 ?s). NiO incorporation in CeO2 results in a decline of operating temperature of NC and improves the sensing features. 相似文献
993.
This study is attempted to develop a green corrosion inhibitor from a waste material of Jack fruit (Artocarpus heterophyllus). This method is therefore quite valuable to health, environment, and economic point of view. Pectin is isolated from the jackfruit peel waste using 0.05 ?N oxalic acid and used as an inhibitor for mild steel corrosion in acidic environment as it is highly water soluble. 250–1000 ?ppm of pectin was used in this study at a temperature range of 303–323 ?K. The protection efficiency of jack fruit pectin (JP) in 0.5 ?M HCl was evaluated by conventional weight loss and electrochemical techniques. The potentiodynamic polarization results revealed that JP could effectively reduce the corrosion of mild steel in acidic medium at 1000 ?ppm concentration with an inhibition efficiency of 89.75% and corrosion rate of 2.392 mpy. The mixed type behavior of the inhibitor is identified from Tafel polarization studies. Electrochemical impedance spectroscopy (EIS) measurements suggest that the corrosion inhibition process is kinetically controlled. adsorption and kinetic behavior of the inhibitor also have been studied. Surface manifestations were followed using FESEM and AFM techniques. DFT calculations and Monte Carlo simulations were also carried out to corroborate the experimental results with theoretical outputs and succeeded to a great extent. 相似文献
994.
Comparative evaluation of antibacterial potentials of nano cobalt oxide with standard antimicrobials
Development of suitable potent antimicrobial is the urgent need of modern era to cope up the problem of antimicrobial resistance. The applications of nanotechnology in metal oxides have shown favorable effects to some extent in this area. Thus, the present study was investigated to evaluate the antibacterial properties of cobalt oxide (Co3O4) nanoparticles at different concentrations and their comparison with standard antimicrobials i.e. tetracycline and gentamicin. Nanoparticles were synthesized and characterized by standard techniques. The antibacterial potentials of Co3O4 nanoparticles against S. aureus and E. coli were determined at various concentrations. The maximum zone of inhibitions of Co3O4 nanoparticles against S. aureus and E. coli at 500 μg/ml were 21.17 mm and 24.00 mm, respectively. The Co3O4 nanoparticles seemed more effective than gentamicin against S. aureus and E. coli. The nanoparticles with respect to tetracycline showed higher than 1 activity index at ≥ 125 μg/ml for E. coli and ≥31.25 μg/ml for S. aureus. It was also higher than 1 at all compared concentrations with respect to gentamicin against both bacteria. In conclusion, Co3O4 nanoparticles seemed to have potent antibacterial potential and these might be very helpful to replace the conventional antimicrobials to solve the problem of antibacterial resistance. 相似文献
995.
Haritha Rajaram N. Harshitha Shweta A. Ram Swarna M. Patra Vidya Niranjan K.A. Vishnumurthy 《印度化学会志》2022,99(6):100488
In the present study, the main protease 3CLpro and non-structural protein (NSP-12 with co-factors 7 and 8) trimer complex are used to study the protein-drug interactions with the phytochemicals from Ocimum Sanctum, Tinospora Cordifolia, Glycyrrhiza Glabra, and Azadirachta Indica. Which can give insight to be used as potent antiviral drugs against SARS-CoV-2. Twenty phytochemicals, five from each plant species, known for their wide range of biological activities were chosen from the literature. The in-silico study was carried out using virtual screening tools and the top five, which showed the least binding energies, were selected. Molecular docking tools revealed that gedunin and epoxy azadiradione proved to be excellent inhibitors for 3CLpro and so did Tinosporide for non-structural-protein complex. Further, the best-hit phytochemicals with respect to structure similarities with FDA drugs and investigatory drugs, were considered for comparative study. Molecular docking was done to check the drug-protein interactions and to check the inhibitory responses of these drugs against the viral protein. The analyses showed that the phytochemicals had similar responses on the protein complex but with exceptionally higher inhibitory responses hence which may be taken for further clinical study. 相似文献
996.
Bharath K. Devendra B.M. Praveen V.S. Tripathi H.P. Prashanth Kumar K.R. Chethana 《印度化学会志》2022,99(6):100466
The current research focused on the development of Platinum–Rhodium alloy coating (Pt– Rh) on SS304 and its applications in antibacterial studies. Electrodeposition is considered to be one of the most suitable methods because it enhances the therapeutic effects of noble metals (Pt–Rh alloy). The electrodeposited coating is an economical and time-saving alternative to existing coating methods. The newly developed Pt–Rh coating was investigated using a scanning electron microscope (SEM) and an atomic force microscope (AFM). Using the agar Petri plate and broth culture method, the antibacterial effect of the platinum-rhodium alloy was investigated against Gram-negative Escherichia coli and Gram-positive bacteria such as Staphylococcus saprophytes, Bacillus Subtilis, and Enterococcus faecalis. The Pt–Rh alloy coated samples obtained by Direct current (DC) and Pulse coating (PC 50% and PC 75%) were examined for antibacterial study. The PC 75% Pt–Rh alloy coating exhibits significant antibacterial activity, demonstrating a maximum zone of inhibition while leaving the rest of the coated samples by DC and PC 50% duty cycles. The study also found that when the concentration of Pt–Rh solution rises from 5 μL to 15 μL, so does the antibacterial activity. The findings of the study showed that electrodeposited platinum-rhodium alloy metal ions may be handy bacteriostatic in the coming years. 相似文献
997.
The present work investigates the best mix ratio of Glycerol in Water as a medium to prepare a stable nanofluid. Increasing the proportion of glycerol enhances the aqueous mix's dynamic viscosity and improves the prepared nanofluid's stability. The thermal conductivity and viscosity of the Glycerol and Water mixtures determination were undertaken at various Glycerol ratios. The best percentage of glycerol in the mixture is found to have the least amount of thermal conductivity loss and the optimum viscosity gain. Silica (SiO2) nanofluid of 0.25%, 0.5%, 1%, and 1.5% weight concentrations was prepared with this optimal mixture of Glycerol and Water. The stability of these SiO2 nanofluids is evaluated by determining the zeta potential at different time intervals. The nanofluids prepared were observed to be stable for one month. The thermal conductivity and viscosity of the nanofluids are measured between the temperature limits of 30°–70°C. A peak increment of 32.1%and 46.3% in thermal conductivity and viscosity is observed. Furthermore, when the percentage enhancement ratio (PER) and Mouromtseff ratio of these nanofluids is examined, it is observed that they have more excellent thermal performance at higher temperatures. Regression correlations are developed to estimate the thermal conductivity and viscosity of the prepared nanofluids with a maximum deviation of 9%. 相似文献
998.
Kumar Mukesh Kumar Pankaj Agrawal Anshu Sahoo B. K. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):715-726
Journal of Radioanalytical and Nuclear Chemistry - Dissolved radon (222Rn) in drinking water has been measured using SMART RnDuo, a continuous radon monitor. Water samples have been collected from... 相似文献
999.
Menel Ben Frej Fanny d'Orlyé Gerson F. Duarte-Junior Wendell K. T. Coltro Anne Varenne 《Electrophoresis》2022,43(20):2044-2048
A low-cost and straightforward hybrid NOA (Norland optical adhesive) 81-glass microchip electrophoresis device was designed and developed for protein separation using indirect fluorescence detection. This new microchip was first characterized in terms of surface charge density via electroosmotic mobility measurement and stability over time. A systematic determination of the electroosmotic mobility (μeo) over a wide pH range (2–10) and at various ionic strengths (20–50 mM) was developed for the first time via the neutral marker approach in an original simple frontal methodology. The evolution of μeo was proved consistent with the silanol and thiol functions arising from the glass and the NOA materials, respectively. The repeatability and reproducibility of the measurements on different microchips (RSD < 14%) and within 15 days (less than 5% decrease) were successfully demonstrated. The microchip was then applied for the efficient electrophoretic separation of proteins in a zonal mode coupled with indirect fluorescence detection, which is, to our knowledge, the first proof of concept of capillary zone electrophoresis in this hybrid microsystem. 相似文献
1000.
Patra Kankan Sengupta Arijit Mishra R. K. Mittal V. K. Valsala T. P. Kaushik C. P. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(3):1473-1481
Journal of Radioanalytical and Nuclear Chemistry - Efficient and selective extraction of 137Cs and 90Sr from high level liquid waste (HLLW) is of utmost importance in the back end nuclear fuel... 相似文献