Curcumin-Chitosan Nanocomposite Formulation Containing Pongamia pinnata-Mediated Silver Nanoparticles, Wound Pathogen Control, and Anti-Inflammatory Potential

Background. Because of its diverse range of use in several ethics of diagnosis and care of multiple diseases, nanotechnology has seen remarkable growth and has become a key component of medical sciences. In recent years, there has been rapid advancement in medicine and biomaterials. Nanomedicine aids in illness prevention, diagnosis, monitoring, and treatment. Aim. The purpose of this work is to evaluate the antibacterial, anti-inflammatory, and cytotoxic capabilities of green produced silver nanoparticle with the addition of curcumin-assisted chitosan nanocomposite (SCCN) against wound pathogenic as reducing agents. Materials and Methods. The plant extract of Pongamia pinnata, silver nanoparticles, and its based curcumin nanoformulations was studied in this study utilizing UV visible spectrophotometer, selected area electron diffraction (SAED), and TEM. Anti-inflammatory, antimicrobial, and cytotoxic tests were performed on silver nanoparticles with the addition of curcumin-assisted chitosan nanocomposite (SCCN). Furthermore, these produced nanocomposites were coated on clinical silk and tested for antibacterial activity. Results. The produced silver nanoparticle with the addition of curcumin-assisted chitosan nanocomposite (SCCN) has significant antibacterial activities against Pseudomonas aeruginosa and staphylococcus aureus. They are as well as possess anti-inflammatory activity and furthermore prove to be biocompatible. Conclusion. This advancement in the field of biomaterials, which means nanocomposite, not only helps to reduce the harmful effects of pathogenic organisms while representing an environmentally benign material but it also shows to be a material with zero danger to humans and the environment.

Does Size Matter? Toxicity Effects of 5‐nm and 70‐nm Silver Nanoparticles on Hoplobatrachus Rugulosus Frog

With the increased usage of silver nanoparticles (AgNPs), the potential impacts of released AgNPs in the environment are increasingly concerned, especially to natural living organisms. Since the properties of AgNPs significantly depend on their sizes, this work aimed to compare the effects of 5-nm and 70‐nm AgNPs on toxicity and bioaccumulation in Hoplobatrachus rugulosus, the edible East Asian Bullfrog. The synthesized AgNPs were characterized by X‐ray diffraction and selected area electron diffraction analyses. Both 5‐nm and 70‐nm AgNPs caused mortality, reduced growth, induced abnormal development, generated cellular oxidative stress, and modulated cellular biomolecule pattern of frog embryos, but at different levels. The 5‐nm AgNPs caused harmful effects on the frog embryos more than 70-nm AgNPs, likely due to their small size to allow more accessibility into the cell. The mortality effects of AgNPs depended on the concentration, exposure time, and size. The malformation of frog embryos in response to AgNPs-exposure included scoliosis, lordosis, kyphosis, and yolk sac edema. Synchrotron Fourier transformed infrared analyses revealed that 5‐nm AgNPs significantly changed the profile of cellular biomolecules in the embryos, indicated by the spectral peaks assigned to lipid, carbohydrates, proteins, and nucleic acids. The bioaccumulation of silvers was dominant in eggs, followed by stomach, liver, kidney, and intestine, respectively, suggesting their translocation via blood circulation. The result of high accumulated silver in eggs and effects on embryonic mortality, growth, development, and cellular changes suggested the potential negative impacts of AgNPs on the sustainability of this frog in the environment.

High Resolution Powder Electron Diffraction in Scanning Electron Microscopy

A modern scanning electron microscope equipped with a pixelated detector of transmitted electrons can record a four-dimensional (4D) dataset containing a two-dimensional (2D) array of 2D nanobeam electron diffraction patterns; this is known as a four-dimensional scanning transmission electron microscopy (4D-STEM). In this work, we introduce a new version of our method called 4D-STEM/PNBD (powder nanobeam diffraction), which yields high-resolution powder diffractograms, whose quality is fully comparable to standard TEM/SAED (selected-area electron diffraction) patterns. Our method converts a complex 4D-STEM dataset measured on a nanocrystalline material to a single 2D powder electron diffractogram, which is easy to process with standard software. The original version of 4D-STEM/PNBD method, which suffered from low resolution, was improved in three important areas: (i) an optimized data collection protocol enables the experimental determination of the point spread function (PSF) of the primary electron beam, (ii) an improved data processing combines an entropy-based filtering of the whole dataset with a PSF-deconvolution of the individual 2D diffractograms and (iii) completely re-written software automates all calculations and requires just a minimal user input. The new method was applied to Au, TbF3 and TiO2 nanocrystals and the resolution of the 4D-STEM/PNBD diffractograms was even slightly better than that of TEM/SAED.

Electrochemical Formation of Elemental Boron in LiCl–KCl–KBF4 at 723 K

The electrochemical reduction behavior of B(III) ions was investigated in LiCl–KCl–KBF4 at 723 K. The results of cyclic voltammetry using Mo, Ag, and Ni electrodes suggested the reduction of B(III) to B(0) at potentials of 1.5 V or at a more negative potential (vs. Li+/Li). Spherical electrodeposits were observed after potentiostatic electrolysis at 1.1–1.5 V. From the results of X-ray photoelectron spectroscopy, scanning transmission electron microscope/energy-dispersive X-ray spectroscopy (STEM/EDX), and selected area electron diffraction, it was concluded that the spherical electrodeposits obtained at 1.1 V were elemental amorphous boron. The purity of the products was 85 wt% boron, as determined by STEM/EDX analysis. The current efficiency of elemental B electrodeposition was 96.2% in this system. The formation of Ni2B at 1.1–1.9 V was indicated by X-ray diffraction, although it was not the main product. These results indicate that the presence of B(III) ions in a melt causes a fatal adverse effect on the recycling process of Nd–Fe–B magnets due to the reduction of B(III) ions. Further, the possibility of reducing the energy and cost of the elemental boron production process was discussed.

Chemical vapor deposition of germanium-rich CrGex nanowires

Chemical vapor deposition was applied to synthetize nanostructured deposits containing several sorts of nanoobjects (i.e., nanoballs, irregular particles, and nanowires). Analytical techniques, that is, high-resolution transmission electron microscopy, scanning electron microscopy, electron dispersive X-ray analysis, selected area electron diffraction, and X-ray photoelectron spectroscopy, showed that unlike nanoballs and particles composed of crystalline germanium, the layer was made of chromium germanide CrGex. The nanowires possessed a complex structure, namely a thin crystalline germanium core and amorphous CrGex coating. The composition of the nanowire coating was [Cr]/[Ge] = 1:(6–7). The resistance of the nanowire–deposit system was estimated to be 2.7 kΩ·cm using an unique vacuum contacting system.

Morphology of metallic foams synthetized by plasma electrolysis deposition

The aim of our work is to understand the mechanism governing the growth of metallic foams synthetized by plasma electrolysis deposition. This paper reports the influence of the applied voltage on the morphology and microstructure of copper and gold foams. The evolution of strands morphology and size is investigated by field emission scanning electronic microscopy (FE-SEM). The role of the voltage in the growth of metallic foams is then discussed. Finally, the crystalline structure of the strands is determined by transmission electronic microscopy (TEM) and selected area electron diffraction.

Formation pathways of oriented magnetite micro-inclusions in plagioclase from oceanic gabbro

Plagioclase hosted needle- and lath-shaped magnetite micro-inclusions from oceanic gabbro dredged at the mid-Atlantic ridge at 13° 01–02′ N, 44° 52′ W were investigated to constrain their formation pathway. Their genesis is discussed in the light of petrography, mineral chemistry, and new data from transmission electron microscopy (TEM). The magnetite micro-inclusions show systematic crystallographic and shape orientation relationships with the plagioclase host. Direct TEM observation and selected area electron diffraction (SAED) confirm that the systematic orientation relations are due to the alignment of important oxygen layers between the magnetite micro-inclusions and the plagioclase host, a hypothesis made earlier based on electron backscatter diffraction data. Precipitation from Fe-bearing plagioclase, which became supersaturated with respect to magnetite due to interaction with a reducing fluid, is inferred to be the most likely formation pathway. This process probably occurred without the supply of Fe from an external source but required the out-diffusion of oxygen from the plagioclase to facilitate partial reduction of the ferric iron originally contained in the plagioclase. The magnetite micro-inclusions contain oriented lamellae of ilmenite, the abundance, shape and size of which indicate high-temperature exsolution from Ti-rich magnetite constraining the precipitation of the magnetite micro-inclusions to temperatures in excess of ~ 600 °C. This is above the Curie temperature of magnetite, and the magnetic signature of the magnetite-bearing plagioclase grains must, therefore, be considered as the thermoremanent magnetization.

Van Der Waals Epitaxial Growth of Bismuth Thin-film on Silicon (111) Substrate by MBE

Crystallinity of an 80-nm-thick bismuth thin film grown on Si(111) substrate by MBE was investigated. The highly (0003) textured Bi film contains two twinning domains with different bilayer stacking sequences. The basic lattice parameters c and a as well as b, the bilayer thickness, of the two domains were determined from a series of X-ray diffraction (XRD) measurements, and found that the differences are within 0.1% as compared with those of bulk Bi reported in literature, suggesting that the Bi film has been nearly fully relaxed. From the XRD φ-scans of asymmetric Bi (01-14), (10-15), (11-26) planes and Si (220) plane as well as selected area electron diffraction patterns and electron back scatter diffraction pole figures, we confirmed the well registration between the lattices of Si and Bi lattice, i.e. the ω angle difference between Bi[0003] and Si[111] and the φ angle different between Bi[01-14] and Si[220] are 0.056° and 0.25°, respectively, and thus concluded that the growth is a quasi-van der Waals epitaxy.

BiOCl nanomaterials for photocatalytic degradations of nitrogenous organic compound

Different BiOCl hierarchical nanostructures with controllable morphologies were synthesized by a facile glycerol-mediated solvothermal method. Every products were subsequently and well crystallized characterized by a range of methods, such as scanning electron microscopy (SEM), X-ray powder diffraction (XRD), high-resolution transmission microscopy (HRTEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED). The photocatalytic properties of the samples were further investigated through photocatalytic decomposition of Methyl Orange (MO) dye. The BiOCl hierarchical nanostructures was as a result of efficient photocatatlytic activity under UV light irradiation, which can degrade MO in a few minutes.

Effects of Variation in Al Content on the Emission of Eu Doped CaAlSiN3 Red Phosphor Synthesized by Combustion Synthesis Method for White LEDs

Effects of Al content on the formation and the photoluminescence properties of CaAlSiN3:Eu2+ phosphor (CASIN) were investigated by a combustion synthesis method. XRD (X-ray diffraction), combined with PL (photoluminescence), TEM-EDS (transmission electron microscope equipped with an energy-dispersive X-ray spectroscope), and SAED (selected area electron diffraction) measurements, show that the bar-like CASIN gives a stronger emission than the plate-like and agglomerated fine particles. The emission intensity increases as the Al content increased from Al = 0.2 to Al = 0.8, which resulted from the extent of formation of CASIN increases. Then, the emission intensity decreases as the Al content is increased from Al = 0.8 to Al = 1.5, which resulted from the transformation of morphology of CASIN and a large amount formation of AlN. In addition, the extent of formation of CASIN increases with increasing Al from Al = 0.2 to Al = 1.2 and begins to decrease as Al is further increased to 1.5, and thus the peak emission wavelength increases from 647 nm to 658 nm as the Al molar ratio is increased from 0.2 to 1.2 and begins to decrease when further increasing the Al molar ratio to 1.5, which resulted from the large amount of AlN formed.