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Green technology is gaining importance nowadays, it has become very important to synthesize various nanoparticles. This review mainly focuses on the phytosynthesis of silver nanoparticles (AgNPs) and shows their catalytic applications in the field of wastewater treatment. Plant-assisted synthesis of AgNPs has been documented by numerous studies. Plant-mediated synthesis has many advantages over conventional methods and is discussed comprehensively in this review. This critical review aims to help researchers to better understand and follow this rapid, cost-effective, and eco-friendly research area. Dye effluents in water bodies become a major environmental issue worldwide. This paper also offers a thorough understanding of the synthetic dyes such as Rhodamine B, Methylene Blue, Crystal violet, Methyl Orange, and Amido black 10B used in the textile industry, with a focus on the popular methods to degrade them from industrial wastewater, especially, chemical degradation, and photocatalytic dye degradation using silver nanoparticles and other Ag-systems. Additionally, the plausible mechanism involved in chemical and photocatalytic degradation was also provided. There are several review articles on all these topics, but such an in-depth study has not been investigated so far in the concerned research literature. [ABSTRACT FROM AUTHOR]

Aim: The precise estimation and replication of skin color are crucial for maxillofacial prosthesis. The study aimed to evaluate facial skin color with a colorimeter and suggest a skin shade guide and formula for color estimation. Settings and Design: An observational study conducted in the department of prosthodontics. Materials and Methods: Study was conducted on 368 individuals of Indian origin in age range of 20–45 years. The facial skin color was assessed in malar regions using SkinColorCatch colorimetric device and individual topography angle (ITA) and CIELAB L*a*b* values were noted. Statistical Analysis Used: K-means clustering was utilized to propose a shade guide for maxillofacial prosthesis with 24 skin shades. Logistic regression analysis was conducted to propose a formula to estimate skin shade of the individuals. Results: Based on cluster analysis, 368 subjects were divided into three clusters with similar characteristic as Cluster 1 with dark skin color in 88 (23.91%) subjects, Cluster 2 with medium skin color in 224 (60.87%) subjects, and Cluster 3 with light skin color in 56 (15.22%) subjects. The mean ITA and L*a*b* values for cluster 1 were −47.04° ±14.77°, 34.53 ± 4.31, 8.55 ± 2, 11.42 ± 3.7033, respectively. The mean ITA angle and L*a*b* values for Cluster 2 were 4.29° ±11.34° 51.67 ± 3.42, 8.79 ± 3.13, 21.36 ± 2.38, respectively. The mean ITA and L*a*b* values for Cluster 3 were 34.65 ± 4.29°, 62.66 ± 3.08, 6.53 ± 1.79, 17.73 ± 2.39, respectively. The proposed shade guide comprised a total of 24 different shades that were categorized into three primary colors according to three distinct clusters, each of which was further broken down into eight subclusters containing various shades within each cluster. Logistic regression analysis gave an equation as follows: Y =12.43 + 0.186X (Y = Predicted skin color, X = ITA angle). Conclusions: Twenty-four facial skin shade tabs have been proposed based on ITA angle and CIELAB values. This comprehensive approach to categorize the shades will ensure a detailed and organized system for selecting and matching colors in maxillofacial prosthesis. [ABSTRACT FROM AUTHOR]

A novel class of nanomaterials known as carbon quantum dots (CQDs) has drawn significant attention because of numerous benefits, particularly its small size (between 1 and 10 nm) and great water solubility, fluorescence, ease of synthesis, and low toxicity among others. There are still many crucial questions that need to be answered, such as how to prepare high-quality CQDs with an appropriate yield using a simpler and easier approach. Most of the articles reviewed have discussed the production of CQDs intended for applications in imaging and sensing. Nevertheless, there is a scarcity of research focusing on producing undecorated and doped CQDs. In this review paper, the various methods for synthesizing CQDs by using various carbon sources have been summarized. Additionally, In this paper, we discuss the primary characterization techniques and the applications of CQDs in various fields. The fundamental objective of this paper is to analyze various synthesis methods used over different periods to address the challenges that one might encounter during the synthesis of CQDs. [ABSTRACT FROM AUTHOR]

We have fabricated the most versatile MAl2O4 (M=Zn, Mg, Ca) spinel nanopowder by citrate sol–gel method using ethylene glycol as a chelating compound. X-ray diffraction method has been employed to analyze the crystalline behavior of prepared nanopowders. The sample annealed at 800 °C indicates the cubic phase for zinc and magnesium aluminates while the monoclinic phase has been noticed for calcium aluminates. Structural parameters like d-spacing, lattice constant 'a', microstrain, stacking fault were evaluated for prepared nanopowders. The Debye–Scherrer formula is being used to calculate the prepared powder's crystallite size, which is further compared with the results of W–H analysis. Surface morphology and elemental composition were examined by SEM–EDS. Methyl blue dye has been selected for evaluating the degradation efficiency of aluminates under sunlight. The study reveals that ZnAl2O4 has the highest degradation efficiency (~ 98%) owing to its large surface area, optimum bandgap, and suitable nanocrystalline size. [ABSTRACT FROM AUTHOR]

Indian citrus ringspot virus (ICRSV) is known to cause serious problem in Kinnow (Citrus nobilis Lour × C. deliciosa Tenora). This paper reports the elimination of ICRSV from Kinnow by chemotherapy coupled with shoot tip grafting under in vitro conditions. Nodal segments from infected mother plant (indexed by indirect ELISA and RT-PCR) were cultured on MS medium containing 2-iP (1mg/l) and malt extract (800 mg/l) along with different concentrations of five antiviral chemicals acycloguanosine, azidothymidine, 2,4-dioxohexahydro-1, 2,5-triazine (DHT), ribavirin and 2- thiouracil. Shoot tips of size 0.7 mm were excised from the sprouts of these nodal segments and grafted on to rough lemon (Citrus jambhiri) under aseptic conditions. The plantlets obtained from chemotherapy coupled with in vitro micrografting were indexed by indirect ELISA and RT-PCR after acclimatization. Maximum effect (37% virus elimination) was seen for ribavirin at 25 mg/l followed by 2-thiouracil at 25 mg/l (21.4%) and acyclguanosine at 25 mg/l (20.8%). Azidothymidine and DHT at the tested doses could not eliminate ICRSV. In the present study only those plants/plantlets were considered virus free, which showed negative reaction both with indirect ELISA and RT-PCR.

Advanced corrosion protection methods include covering stainless steel surfaces with conductive polymer-based coatings. Polypyrrole and polypyrrole composites of tungstate of different concentrations were deposited on stainless steel-304 using cyclic voltammetry and their elemental analysis was verified by EDX analysis. EIS and potentiodynamic polarization analysis show that the corrosion protection efficiency (CPE) of polypyrrole composites is higher than polypyrrole coating. The reduction in corrosion rate due to the inhibitory action of tungstate through the physical barrier and anodic protection mechanism was validated by greater Rct and lower Icorr values of polypyrrole composites. In the composites, with increasing the concentration of tungstate in polypyrrole from 5% to 15%, CPE also increases, as polypyrrole composites are more able to shift the corrosion potential of stainless steels towards the passive zone and form a new nonporous passive oxide film on the surface. With a 15% concentration coating, the highest CPE of 93% and the lowest corrosion rate of 130 mmpy were obtained, indicating that the entire stainless steel active surface area is completely absorbed and that no active sites exit for adsorption at this concentration. The synthesized polypyrrole composites with a 15% concentration offer excellent corrosion protection prospects. [ABSTRACT FROM AUTHOR]

Spinel MgAl2O4 nanopowder synthesized by a novel citrate sol–gel process followed by annealing at different temperatures has been explored. Thermogravimetric and differential thermal analyses have been used to investigate the thermal qualities, and confirmed the best annealed temperature (1073 K). x-ray diffraction was used to examine the crystallinity and phase purity for the annealed samples. Fourier-transform infrared spectroscopy and electron microscopy (SEM-TEM) identified the functional groups and their morphology. The optical absorption data infer 5.12–1.8 eV band gap values (Eg) which can be significantly tailored via annealing. The thermal dependency of the emission spectra has been successfully demonstrated at two excitations, i.e. band-to-band excitation and defect-related. At 225 nm (Eg < Eex) excitation, the emissions were in the violet-blue region, while at 325 nm (Eg > Eex) excitation, green-orange transitions dominated. The prominent emissions were further emphasized by specific color coordinates in their CIE chromaticity graphs. The annealed MgAl2O4 spinel has a higher decay constant due to an increase in radiative centers. The electronic trapping–detrapping mechanism in the overall emissions is contributed by band-to-band excitonic, shallow traps and deep states, and is also comprised of induced antisites transitions. [ABSTRACT FROM AUTHOR]

Supercapacitors (SCs) are esteemed as an intriguing technological for advanced energy storage in the impending era, owing to their intrinsic safety attributes and their unique features such as quick charging, good permeability, extended life-cycle, high power density (P d), thermal durability, and large specific surface area (SSA). Besides these properties, commercial SCs have certain drawbacks, such as low energy density, sustainability, environmental footprint, and energy at low cost. To improve the efficacy of SCs, CQDs (Carbon Quantum Dots) are a novel family of 0-D carbon nanoparticles, with a dimension of <10 nm, a new and emerging precursor to developing electrode nanomaterial for energy storage devices. Here's a review, we summarized the various types of green-source derived CQDs precursors, (plant parts, agro-waste, waste materials, micro-organisms, etc.) to synthesize electrode constituents for SCs, different methods of synthesis, and properties. This analysis explains a detailed outlook of various types of hybrid materials and their effect on the performance of SCs, alongside their captivating utilizes in the area of SCs. A systematic examination of important variables like electrode material, electrolyte, pore size, potential range, and temperature that influence the mechanisms of the SCs is also included in this extensive review. • Synthesis of green sources-based carbon quantum dots as electrode material in supercapacitor. • Preparation of CQDs composites to improve the electrochemical properties of supercapacitors. • Key factors affecting the performance of supercapacitors. [ABSTRACT FROM AUTHOR]