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Various concentrations of samarium‐grafted‐carbon nitride (Sm‐g‐C3N4) doped‐bismuth oxobromide (BiOBr) quantum dots (QDs) are prepared by the co‐precipitation method. Elemental evaluation, morphological, optical, and functional group assessment are studied employing characterization techniques. Based on the XRD pattern analysis, it is determined that BiOBr exhibits a tetragonal crystal structure. The electronic spectroscopy revealed an absorption peak for BiOBr at 315 nm and the bandgap energy (Eg) decreasing from 3.9 to 3.8 eV with the insertion of Sm‐g‐C3N4. The presence of vibrational modes related to BiOBr at 550 cm−1 is confirmed through FTIR spectra. TEM revealed that pure BiOBr possessed non‐uniform QDS, and agglomeration increased with the addition of Sm‐g‐C3N4. The catalytic performance of Sm‐g‐C3N4 into BiOBr (6 mL) in a neutral medium toward rhodamine B exhibited excellent results (99.66%). The bactericidal activity is evaluated against multi‐drug resistance (MDR) Escherichia coli once the surface area is increased by dopant and the measured inhibition zone is assessed to be 3.65 mm. Molecular docking results supported the in vitro bactericidal potential of Sm‐g‐C3N4 and Sm‐g‐C3N4 doped‐BiOBr as DNA gyraseE. coli inhibitors. This study shows that the novel Sm‐g‐C3N4 doped‐BiOBr is a better catalyst that increases specific semiconductor's catalytic activity (CA). [ABSTRACT FROM AUTHOR]

The classical co-precipitation technique was carried out for the preparation of cobalt ferrite (CFN), and Ag-doped cobalt ferrite (AgCFN). Composite with graphitic carbon nitride (AgCFN@gCN) was prepared by employing the ultrasonication method. Photocatalytic degradation activity of synthesized materials was evaluated using crystal violet (coloured compound) and benzimidazole (colourless compound) under sunlight. Various physiochemical methods such as UV–Visible, XRD, SEM, and FT-IR spectroscopy were employed for the characterization of prepared samples. XRD was used for structural characterization. The prepared nanomaterials were sized up to be < 09 nm. FT-IR spectroscopy was exploited for the functional group characterization. Surface morphology was perceived through Scanning Electron Microscope. Optical analysis was carried out using a UV–Visible spectrophotometer. The photodegradation efficiencies for crystal violet and benzimidazole were ascertained to be in the order of CFN < AgCFN < AgCFN@gCN, under sunlight. Among the synthesized photocatalysts, AgCFN@gCN was discovered to have the highest photocatalytic degradation efficiency of 52.72% and 84.21% for benzimidazole and crystal violet, respectively. The higher catalytic activity of AgCFN@gCN can be associated with its high surface area and the presence of active sites of the gCN sheets. Role of electrons (e−), holes (h+), and hydroxyl radicals (O H ∗ ) in the photocatalytic activity was also assessed. [ABSTRACT FROM AUTHOR]

In order to study any material the first principles approach has been considered an appropriate forum and deemed the best remedy to ensure the validity of the achievements/results obtained either theoretically or experimentally. We are, therefore, motivated to use this approach to explore the structural, optoelectronic and vibrational properties of Sb2S3 while utilizing the plane-wave pseudopotential technique and conjugate gradient method employed through the CASTEP simulation code. The crystal structure of Sb2S3 is optimized in orthorhombic phase having space group Pnma with lattice parameters a = 11.31 Å, b = 3.84 Å and c = 11.23 Å. It is noticed that magnitude of these lattice parameters approximately replicate the formerly reported theoretical as well as experimental results. The energy band gap is found to be 1.012 eV, which is utter evidence that the studied compound belongs to semiconductor category of the materials. The optical parameters unveil that Sb2S3 is capable to absorb wide range of radiations from the ultraviolet (UV) portion of the spectrum. The dynamical analysis through density functional perturbation theory (DFPT) shows that there is no soft mode which further ensures dynamical stability of Sb2S3. The optical analysis of the studied compound are enough to declare it a potential material for applications in solar cells. [ABSTRACT FROM AUTHOR]

Recent studies are confirmed that lead-free perovskite is a possible alternative solution for conventional hybrid lead-based perovskites to achieve better photovoltaic efficiency. This work investigates the structural, mechanical, electronic, and optical properties of vacancy ordered double perovskite of K2PdX6 (X = Cl, Br, I) for photovoltaic applications through the density functional theory at the HSE06 level of theory. The bond length of Pd-X is linearly increased while exchanging the anions from Cl to I. The mechanical study reveals that the vacancy-ordered double perovskites K2PdCl6, K2PdBr6, and K2PdI6 are elastically classified as ductile materials. The K2PdBr6 hold a favourable bandgap of 1.62 eV for single junctions solar cell applications. The studied perovskite bandgaps depend on the Pd-4d, s and p orbitals of anions. The optical study uncover that the studied perovskites are higher optical absorption in the visible regions. Based on calculated results, we conclude that these K2PdBr6 vacancy ordered double perovskites might be suitable material for photovoltaic applications. [ABSTRACT FROM AUTHOR]

The dust grain surface potential is examined analytically and numerically in dusty plasmas containing negative/positive ion species by using the Cairn Tsallis (non-Maxwellian) dusty plasma. The equations for the dust-charging process are derived to solve the current balance equation for the xenon–fluorine–sulfur hexafluoride and argon–fluorine–sulfur hexafluoride plasmas. The charging process affected by plasma properties such as spectral indices α and q, in addition to positive ion streaming ( U A r + and U X e + ) and negative ion streaming ( U F − and U S F 6 − ) of both types of plasmas, is examined. Our findings suggest that considering a wide range of X e + − F − − S F 6 − and A r + − F − − S F 6 − masses is critical for understanding plasma physics, specifically multi-component plasmas. [ABSTRACT FROM AUTHOR]

This study used a supported liquid membrane system (SLM) using Celgard 2400 polypropylene as the support, di(2-ethylhexyl) phosphoric acid (D2EHPA) as the carrier, and kerosene as the diluent. To obtain the best carrier concentration, D2EHPA concentrations between 0.04 and 0.6 M were used. The Cr (III) solutions used in the feed phase had various ionic strengths and were adjusted with NaCl at concentrations ranging from 0.25 to 1.75 M. To maintain a constant pH (4) in the feed phase, a 0.2 M acetic acid–sodium acetate buffer was utilized. Because the rate of Cr (III)-carrier complex formation at the interface of the feed solution and membrane increased up to 20 × 10−4 mol/L, it was discovered that transport of Cr (III) rose with an increase in chromium content in the feeding phase. For the optimization of the various stripping agents, HCl concentration was employed, from 0.25 M to 1.75 M. It was observed that Cr (III) transport increased with the increase in HCl concentration because the transport was at a pH gradient, which was the main driving force. Because of the fact that at the feed phase-membrane contact, D2EHPA combined with chromium ions to form the Cr (III)-carrier complex and released H+ protons, in the feed phase, the Cr (III)-carrier complex was diffused into a stripping phase, wherein Cr (III) ions were stripped and the carrier was reversibly protonated again. [ABSTRACT FROM AUTHOR]

Amylase and glucosidase enzymes are the primary harmful source in the development of the chronic condition known as diabetes mellitus. The main function of these enzymes is to break the macromolecules into simple sugar units which are directly involved in the solubility of blood, hence increasing blood glucose levels. To overcome this effect, there is a need for a potent and effective inhibitor that inhibits the conversion of macromolecules of sugar into its smaller units. In this regard, we synthesized thiazolidinone-based indole derivatives (1–20). The synthesized derivatives were evaluated for α-amylase and α-glucosidase inhibitory activity. Different substituted derivatives were found with moderate to good potentials having IC50 values ranging, for α-amylase, from 1.50 ± 0.05 to 29.60 ± 0.40 μM and, for α-glucosidase, from IC50 = 2.40 ± 0.10 to 31.50 ± 0.50 μM. Among the varied substituted compounds, the most active analogs four (1.80 ± 0.70 and 2.70 ± 0.70), five (1.50 ± 0.05 and 2.40 ± 0.10, respectively) of the series showed few folds better inhibitory activity than standard drug acarbose (IC50 = 10.20 ± 0.10 and 11.70 ± 0.10 μM, respectively). Moreover, structure–activity relationship (SAR) was established and binding interactions were analyzed for ligands and proteins (α-amylase and α-glucosidase) through a molecular docking study. [ABSTRACT FROM AUTHOR]

By using the chemical bath deposition approach, binary bismuth sulphides (Bi2S3) and chromium-doped ternary bismuth sulphides (Bi2−xCrxS3) thin films were effectively produced, and their potential for photovoltaic applications was examined. Structural elucidation revealed that Bi2S3 deposited by this simple and cost-effective method retained its orthorhombic crystal lattice by doping up to 3 at.%. The morphological analysis confirmed the crack-free deposition, hence making them suitable for solar cell applications. Optical analysis showed that deposited thin films have a bandgap in the range of 1.30 to 1.17 eV, values of refractive index (n) from 2.9 to 1.3, and an extinction coefficient (k) from 1.03 to 0.3. From the Hall measurements, it followed that the dominant carriers in all doped and undoped samples are electrons, and the carrier density in doped samples is almost two orders of magnitude larger than in Bi2S3. Hence, this suggests that doping is an effective tool to improve the optoelectronic behavior of Bi2S3 thin films by engineering the compositional, structural, and morphological properties. [ABSTRACT FROM AUTHOR]

This study presents the photon shielding factors, viz, the linear attenuation (LAC) and mass (MAC) attenuation coefficients, half-value layer (HVL), transmission factor TF, and effective atomic number Z eff of xCo2O3-(100 − x)[80 TeO2–19Li2O–1ZrO2] glass–ceramic system (for 0 ≤ x ≤ 20 mol%) synthesized by the melt-quench method. The parameters were estimated using FLUKA simulations and compared with WinXCOM calculations for low photon energies in the range 241–2510 keV. Generally, LAC values smoothly decline with photon energy with highest (lowest) value at minimum (maximum) energy. The corresponding highest (lowest) values of LAC was 0.961 (0.205), 0.955(0.206), 0.911 (0.205), and 0.853 (0.205) cm−1 for Co2O3 concentration of 0–20 mol%. The HVL values of CoTeLiZr1 and CoTeLiZr4 samples equaled 0.72 cm and 0.81 cm, correspondingly, at photon energy 284 keV and both increased to 3.38 cm at 2506 keV. At minimum (maximum) photon energy, Zeff value was obtained as 27.94 (19.27), 27.73 (19.16), 26.08 (18.35), and 24.06 (17.59) for CoTeLiZr1, CoTeLiZr2, CoTeLiZr3, and CoTeLiZr4, respectively. Analysis of all estimated parameters shows that the gamma photon shielding efficiency improves according to the trend CoTeLiZr1 > CoTeLiZr2 > CoTeLiZr3 > CoTeLiZr4. The partial replacement of TeO2 with CoO3 leads to the decline in the photon shielding efficacy and mass density of the glass–ceramics. The CoTeLiZr1–4 exhibit substantially enhanced shielding efficiency with respect to ordinary concrete, barite concrete, and RS-253-G18 commercial shield. The present materials thus have great potential as gamma photon absorbers in nuclear facilities where low energy photons are applied. [ABSTRACT FROM AUTHOR]

Spent Ni–Cd batteries are now considered an important source for many valuable metals. The recovery of cadmium, cobalt, and nickel from spent Ni–Cd Batteries has been performed in this study. The optimum leaching process was achieved using 20% H2SO4, solid/liquid (S/L) 1/5 at 80 °C for 6 h. The leaching efficiency of Fe, Cd, and Co was nearly 100%, whereas the leaching efficiency of Ni was 95%. The recovery of the concerned elements was attained using successive different separation techniques. Cd(II) ions were extracted by a solvent, namely, Adogen® 464, and precipitated as CdS with 0.5% Na2S solution at pH of 1.25 and room temperature. The extraction process corresponded to pseudo-2nd-order. The prepared PTU-MS silica was applied for adsorption of Co(II) ions from aqueous solution, while the desorption process was performed using 0.3 M H2SO4. Cobalt was precipitated at pH 9.0 as Co(OH)2 using NH4OH. The kinetic and thermodynamic parameters were also investigated. Nickel was directly precipitated at pH 8.25 using a 10% NaOH solution at ambient temperature. FTIR, SEM, and EDX confirm the structure of the products. [ABSTRACT FROM AUTHOR]

Structural, electronic, elastic and magnetic properties of Ln3QIn (Ln = Ce, Pr and Nd; Q = C and N) anti-perovskites were studied using density functional theory. The measured structural parameters were much reliable with experiments and decreased with the contraction of atomic radii of R and Q atoms. Electronic properties show that the overlapping of Ln-f states around the Fermi level is responsible for the metallic property of these compounds. The electrical resistivity of these compounds shows that the compounds under study show good conductivity at 25°C. Elastic properties of these compounds show that they are mechanically stable with an anisotropic and ductile nature. Magnetic susceptibility and magnetic ordering show that all the compounds are A-type antiferromagnetic, having Neel temperatures of 9 K to 12 K, respectively. Due to the antiferromagnetic nature of these compounds, magnetic probes are unable to read the data stored in the antiferromagnetic moments, and data remains unaffected through disturbing magnetic fields. [ABSTRACT FROM AUTHOR]