Inspection of casting defects and grain boundary strengthening on stressed Al6061 specimen by NDT method and SEM micrographs

Dhinakaran²,

Patil

et al. 2022

Low toxicity carbon dots are combating the disadvantages of quantum dots. The carbon dots find their applications in many fields due to their versatile nature. Four different types of carbon dots are present, according to the way of manufacturing and application the type is chosen. The water-soluble characteristics of carbon dots help them be involved in biomedicine applications. The optical properties of the carbon dots find applications as drug delivery, biosensors, LED, etc. The properties like fluorescence, photoluminescence, and phosphorescence are found in the carbon dots. The carbon dots occupy the tiny spot that exhibits different optical properties on excitation. The carbon dots excitation is mainly due to surface states. The characterization of surface states is very complex. The surface states contain the core structure of carbon and oxygen functional groups on the surfaces. The anions and cations formed from functional groups on excitation will recombine themselves. The functional groups are usually carboxyl and hydroxyl groups. The Π-collaborative network of the electronic structure contains many quantization levels which help the carbon dots to produce different wavelengths adapting to different applications. Due to the interference of the structure of the carbon dots, the entire property will vary. Doping of heteroatom methods is employed to enhance the fluorescence, and photoluminescence property carried out. They used N, S, P, and B heteroatoms singly and in combination to doping carbon dots. Here, the paper proposes the sulphur dioxide adsorption technique to enhance the optical properties of the carbon dots. The proposed method shows 8.5% efficiency in relative fluorescence intensity and 8% efficiency in terms of photoluminescence intensity.

“…The P dopant forms surface defects in carbon dots, especially diamond sp 3 surfaces. The B dopant is not widely used, and it has four different categories of processing [33].…”

Section: Absorptionmentioning

confidence: 99%

Surface State Treatment of Carbon Dots Using Sulphur Dioxide Isotherm

Dhinakaran²,

Patil

et al. 2022

“…Such characteristics of activated carbon make it a viable option in pharmaceutical, chemical, food, petroleum, and treatment of industrial, urban, and suburban waters. Activated carbon can remove solid and gaseous wastes and recover vital elements [15]. Wang et al employed activated carbon produced from bamboo and coated with Co.…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Optimization of Cr (VI) Removal from Aqueous Solution by Activated Carbon with Magnetic Fe₃O₄Nanoparticles by Response Surface Methodology

Rajasekaran

Singh

et al. 2022

In this study, the activated carbon with Fe3O4 nanoparticles was synthesized and employed as an effective tool to remove the Cr (VI) from the aqueous solution. The process inputs like concentration of Cr (VI), the dosage of Fe3O4 nanoparticles in activated carbon, and pH of the aqueous solution were optimized by response surface methodology, and their effects were studied. The statistical analysis by ANOVA showed that the process inputs were significantly affected the removal rate, with the maximum impact provided by the pH of the aqueous solution. The best parameters were identified to be pH of 3, aqueous solution concentration of 12 mg/L, the dosage of 1.5 g/L, and adsorption time of 40 min. SEM, EDS, and FTIR characterized the synthesized activated carbon/Fe3O4 samples with magnetic characteristics. Adsorption isotherms and adsorption kinetics analyzed the chemical stability of the synthesized nanocomposite.

“…The quantum confinement effects of ZnO nanowires makes the transport of photons, electrons, and carriers. The ZnO-based nanowires are the richest among the other nanostructures because of their structures and properties [15]. There are two main structures of ZnO nanowires: hexagonal wurtzite and cubic zinc blende.…”

Section: Methodsmentioning

confidence: 99%

Adsorption of SO₂ on ZnO Nanowires Using Activated Carbon by Langmuir Adsorption Isotherm

Nadh

Katubi

et al. 2022

Sulphur dioxide (SO2) is one of the contaminants present in the environment. They are the by-product of combustion, industrial pollution, generation of electricity, etc. After some reactions in the atmosphere, SO2 changes its form and produces acid rain. The presence of SO2 needs to be detected to combat its effect. Many nanosensors are designed to detect the presence of SO2 in the environment. Zinc oxide (ZnO) nanowire sensor is one of those sensors used for SO2 detection. The size, structure, cost-effectiveness, and unique properties made it a choice for sensing purposes. Activated carbon is another compound that has porous substances that helps the adsorbate to settle down on the large surface area of its adsorbent surfaces. Combining the nature of ZnO nanowire and activated carbon, the adsorption of SO2 can be increased. This paper proposes a novel technique involving the activated carbon in the ZnO nanowire sensor to increase its SO2 adsorption capacity and rate. The Langmuir adsorption isotherm is used to find the adsorption efficiency between the solid adsorbent and gaseous adsorbate. MATLAB simulation was carried out for the proposed work in which it is seen that the novel method shows 33.34% efficiency in terms of SO2 adsorption capacity. The response of the proposed sensor shows 23% efficiency over time. The analysis shows that the usage of the activated carbon increases the adsorbent site for SO2 adsorbate to adsorb on the surfaces. According to the adsorption quantity, SO2 level has been obtained in the environment.