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A study was conducted to develop a cost-effective and eco-friendly method for synthesizing silver nanoparticles (AgNPs) using Ocimum Basilicum leaf extract (OBLE). The physical and chemical properties of the synthesized AgNPs were analyzed. The X-ray diffractogram of OBLE-mediated AgNPs (OBLE@AgNPs) exhibited face-centered cubic crystallinity with space group F m 3 ¯ m , which was confirmed by Rietveld refinement studies. Fourier Transform Infrared (FTIR) spectroscopy identified the functional groups of the phytochemicals present in OBLE at 3416 cm−1 and 1652 cm−1, indicating the presence of phenolic (−OH) content belonging to OBLE. The formation of AgNPs was confirmed by a characteristic hump at 403 nm in the UV-Vis spectrum. The granular microstructure of OBLE@AgNPs showed well-interlinked grains with agglomeration and an average grain size of 22 nm. The anticancer activity of OBLE@AgNPs was evaluated against MDA-MD 231 breast cancer cell lines, and the results indicated dose-dependent cell viability with an IC50 value of 67.83 µg/mL. The present study demonstrated a simple and environment-friendly method for synthesizing AgNPs using OBLE, which could potentially be used in various biomedical applications. Highlights: OBLE@AgNPs exhibit face-centered cubic crystal structure with Fm 3 ¯ m space group. OBLE@AgNPs showed well-interlinked grains with an average grain size of 22 nm. FTIR spectrum of OBLE@AgNPs confirmed the presence of phytochemicals of OBLE. Low IC50 (= 67.83 µg/mL) was obtained for the cytotoxic activity of OBLE@AgNPs against MDA-MD 231 cancer cell line. [ABSTRACT FROM AUTHOR]

The worldwide pollution of water bodies by potential contaminants such as heavy metals, dyes, and pesticides etc. have severely affected the entire eco-system due to their toxic mobility and tough degradation in water. Consequently, there is a requirement to develop cost-competitive and easily handleable sensing materials which can detect targets sensitively and with selectivity. Among the low-cost sensory materials, carbon dots (CDs) constitute an important class of carbon nanomaterial with unique photostability, electronic and fluorescent properties. This review is an effort to comprehend the recent improvements in the sensing applications of CDs with prominence on synthetic routes, the effect of various synthesis parameters on physical properties (quantum yield, size range), detection mechanisms, and detection parameters (limit of detection, interference etc.). Particularly, the scope and progress for the detection of potential water contaminants using CDs have been explored and a holistic view of mechanisms of their detection has been included. Holistic view of mechanisms for different types of signals generated by CDs. [ABSTRACT FROM AUTHOR]

Sunlight driven Mnn+-ZnO (n = 2, 4 and 7) nanohybrids were prepared via impregnation method using different metal precursors of variable oxidation state. Dynamic light scattering (DLS) spectra showed that the average hydrodynamic size decreased when precursor of higher Mn oxidation state was used. Moreover, the structural analysis revealed that Mn nanoparticles (5–10 nm, d = 0.13 nm) dispersed over ZnO support (20–30 nm, d = 0.39 nm) while KMnO4 was added for impregnation purpose. Interestingly, the co-catalyst (Mn) was loaded in + 2, +4 and + 7 oxidation state when MnSO4.H2O, MnO2 and KMnO4 respectively utilized for loading over ZnO surface, confirmed from X-ray photon spectroscopy. The potential of prepared nanocomposites were investigated for methylene blue (MB) degradation, an organic pollutant and it was observed that oxidation state of the co-catalyst largely influenced the photoactive-response of nanocomposites. Notably, Mn7+-ZnO degraded MB (98%) nearly 3.3 times higher as compared to bare ZnO and also higher than Mn4+-ZnO (91%) and Mn2+-ZnO (83%). The metal nanoparticles played a dual role in the photo-oxidative reaction by sensitizing the nanomaterial in the sunlight and suppressing the recombination rate of electrons-holes to enhance the reaction efficiency. [ABSTRACT FROM AUTHOR]

Non-Abelian discrete symmetry group S 3 × Z 3 has been used to construct quark mass matrices in the flavor basis. Interestingly, the case when M d is nondiagonal and M u is diagonal, is very much compatible with the presently refined data regarding the quark masses and mixing. However, the other case, when M u is nondiagonal and M d is diagonal, looks to be incompatible with the data. [ABSTRACT FROM AUTHOR]

The present study portrays, a low-cost, environmentally benign, and green route synthesis of Mangifera indica leaf extract mediated silver nanoparticles (MI:AgNPs). MI:AgNPs were characterized using analytical techniques such as X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), UV–Visible spectroscopy, Transmission Electron Microscopy (TEM). The structural characterization revealed that MI:AgNPs exhibited face centered cubic crystallinity with space group F m 3 ¯ m without any traces of impurities and secondary phases. FTIR spectra confirmed the presence of phytochemicals (such as alkaloids, polyphenols, flavonoids, etc.) present in leaf extract, which serves as reducing, stabilizing and capping agent. UV–Vis spectra showed a sharp absorption peak in the UV region belonging to leaf extract and a hump in the visible region (~ 404 nm) attributed to the formation of AgNPs. TEM micrograph showed pseudo-spherical particles with average diameter of 18.2 ± 0.12 nm. MI:AgNPs showed enhanced photocatalytic activity against Methylene Blue (MB) dye under UV radiation. Cytotoxic activity was carried out on cervical cancer cell line (HeLa) at different concentrations of MI:AgNPs, which displayed potent anti-cancerous potential and illustrated the efficacy of MI:AgNPs with a low IC50 value 83.85 ± 9.63 µg/mL. The low-cost synthesis and effective cytotoxic potential of MI:AgNPs can make them an attractive choice for biomedical application. [ABSTRACT FROM AUTHOR]

In the present report, Ce3+ modified SnO2 compositions [Sn(1−y)CeyO2, for y = 0, 0.05, and y = 0.10, where y is wt.% of Ce3+] were synthesized via co-precipitation and their physicochemical properties were investigated. Crystal structure studies were carried out by using Rietveld refinement which confirmed high phase-purity and rutile-type tetragonal crystallinity with a P42/mnm space group (space group no. 136) for all samples. Fourier transform infrared (FTIR) spectroscopy depicted the antisymmetric vibrations of Sn-O-Sn and stretching vibration of Sn-O, which were confirmed by bends located at 636 cm−1, and 460 cm−1, respectively. All the compositions showed a strong hump at ~ 300 nm in the ultra-violet (UV) region and the peak shifts slightly towards the blue region with increasing Ce3+content. Transmission electron microscopy (TEM) micrographs depicted pseudospherical particles with an average particle diameter of 12.84 ± 0.17 nm, 15.55 ± 0.31 nm, and 16.52 ± 0.36 nm for y= 0, 0.05, and 0.10, respectively. High-resolution transmission electron microscopy (HRTEM) images confirmed tetragonal crystallinity for all the compositions. Dielectric studies illustrated that on increasing the concentration of Ce3+ in the host SnO2, the value of dielectric permittivity increased. The value of tanδ is maximum for pristine SnO2. The variation of ac conductivity was due to Maxwell–Wagner type interfacial polarization. For all the compositions, a sharp hump centered at ~ 407 nm was observed in the photoluminescence spectrum, which may be attributed to the presence of oxygen anion vacancies. [ABSTRACT FROM AUTHOR]

In this paper, structural features of quark mass matrices have been analyzed in the flavor basis which is allowed by weak basis transformations in the Standard Model. Using the latest precised data pertaining to quark mixing matrix and small quark masses, we find that the texture structure of these cannot be simplified further. However, we find enormous amount of simplification is possible wherein we have found that a single phase in the mass matrix is adequate to accommodate the CP violating phase of CKM matrix. [ABSTRACT FROM AUTHOR]

In the context of precise measurements in some of the CKM elements and angles of the unitarity triangle coupled with latest theoretical improvements of lattice QCD calculations of "hadronic factors," we have explored the implication of these and unitarity on some of the CKM parameters which are ridden with ambiguities. In particular, we have undertaken a thorough scrutiny of the implications of the precise measurements of the angles of the unitarity triangle along with the element | V u s | , on the | V u b | , | V t d | , | V t s | , as well as the CP violating parameter K . Interestingly, we find a unitarity-based analysis while unambiguously favoring | V u b | exclusive-over-inclusive value which is also in agreement with the present data pertaining to K , | V t d | , | V t s | , Δ M d / Δ M s , etc. The present analysis also shows that the presence of NP in K − K ̄ and B d − B d ¯ systems, if any, would be less than a few percent only. [ABSTRACT FROM AUTHOR]

In the present study, pristine and Cd2+ modified SnO2 compositions [Sn(1−y)CdyO2, where y = 0, 0.05, and 0.10] were synthesized by co-precipitation technique. Structural studies were carried out by X-ray diffraction (XRD) analysis which revealed that all the compositions exhibited tetragonal rutile-type crystal structure with P42/mnm space group with high purity (absence of secondary phases). FTIR spectra confirmed the formation of pristine and Cd2+ modified SnO2 nanocrystals as bend at 560 cm−1 attributed to Sn–O–Sn stretching vibrations. UV–Vis optical spectra displayed a sharp peak at ~ 304 nm and ~ 311 nm belonging to UV region (200–400 nm) and a small hump at 561 nm corresponding to the visible region for Cd2+-doped compositions. FESEM micrographs depicted the nano-scale formation of pristine and Cd2+ modified SnO2 nanocrystals calcined at 600 °C and showed that grain size increased from 45.66 ± 1.2 nm to 60.27 ± 2.7 nm with increasing Cd2+ concentrations. HRTEM images confirmed the tetragonal crystallinity of as-synthesized nanocrystals as fringes attributed to (110) plane orientation with d-spacing ~ 0.34 nm exactly matched with XRD studies. Dielectric analysis showed that dielectric constant decreased with increasing Cd2+ in the compositions and I–V curves illustrated linear or ohmic behavior with diminishing values of resistances for higher Cd2+ concentrations. [ABSTRACT FROM AUTHOR]

A correction to the article "Influence of Ce3+ Modification on Physicochemical Characteristics of SnO2 Nanoparticles" is presented.