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In the present work, zinc sulphide (ZnS) nanoparticles are synthesized via solvothermal route using different capping agents. The sphalerite phase is detected by X-ray diffraction (XRD) analysis. The morphology of the nanoparticles is confirmed by scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). The average particle size is found between 5 and 7 nm as calculated by HRTEM analysis. Energy dispersive X-ray spectroscopy (EDX) specified the desired elemental composition. Bandgap studies are done by UV–visible absorption and the photoluminescence spectroscopy (PL) gives the emission peaks centered at 452 nm and 460 nm. Fourier transform infra-red spectroscopy (FTIR) of ZnS nanoparticles confirmed the presence of various functional groups and showed the encapsulation of capping agents. The cylindrical non-woven network of PAN-ZnS nanofibers synthesized by electrospinning technique as confirmed by SEM and the distribution of nanoparticles in the polymer matrix is confirmed by HRTEM analysis. EDX and FTIR showed the incorporation of ZnS nanoparticles in polymer matrix. The objective of the present work is to synthesize the PAN-ZnS composite nanofibers for antibacterial applications. To the best of our knowledge this type of studies using polyacrylonitrile (PAN) as a polymer are not found in the literature showing the novelty of our work. [ABSTRACT FROM AUTHOR]

Bismuth ferrite with manganese doping (BiFe0.95Mn0.05O3 or BFMO) and bismuth ferrite with cobalt and manganese doping (Bi0.95Co0.05Fe0.95Mn0.05O3 or BCoFMO) were both synthesized as nanocrystalline powders by the sol–gel autocombustion technique. X-ray diffraction examination of the powders indicates a rhombohedral distortion in the perovskite phase in both samples. The calcined powders were examined for their microstructure and elemental composition with high resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray spectroscopy (EDAX), respectively. Scanning electron microscopy (SEM) was used to examine the microstructures of sintered BMFO and BCoFMO specimens at room temperature. Dielectric characteristics were studied at various frequencies and temperatures and found to follow space charge polarization. At ambient temperature, a vibrating sample magnetometer was used to analyse the materials' magnetic behaviour (M–H loops). Saturation magnetization is significantly increased with increased coercivity in the BCoFMO sample compared to the other sample. Improved structural, dielectric, and magnetic values in these doped systems, however, suggest they'd be an excellent fit for spintronic, multifunctional memories, sensors, and actuators. [ABSTRACT FROM AUTHOR]

This research discloses a single step, facile, cost-effective, and eco-friendly fabrication of gold nanoparticles (AuNPs) using the aqueous extract of common reed (Phragmites australis) leaf. Various techniques were employed to characterize the resultant AuNPs such as UV–Vis spectroscopy, high resolution transmission electron microscopy (HRTEM) mapping, fourier transform infrared (FT-IR), Zeta potential, X-ray diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX), and X-ray Photoelectron Spectroscopy (XPS) to confirm the bioformation of AuNPs. The results showed the formation of violet-colored, mainly spherical shaped AuNPs with about 18 nm diameter. The XRD results proved the crystalline structure of AuNPs. Furthermore, P. australis-AuNPs exhibited notable anticancer efficacy with an IC50 equals 129 μg/mL, good quenching for DPPH free radical with a scavenging percentage equals 10.26% and a superior photocatalytic activity as they completely removed methylene blue in just 1 min. The current study also provides an open option for the environmental management of the unwanted biomass of common reed. [ABSTRACT FROM AUTHOR]

In this work, a magnetically separated photocatalyst with great efficiency CuCe-Ferrite/TiO2 composite was prepared and characterized by X-ray diffraction (XRD), UV–Vis spectrophotometry, Fourier transformer infra-red spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), energy dispersive X-ray spectroscopy (EDX) and vibrating sample magnetometer (VSM). Single-phase cubic spinel was formed by calcining the prepared sample at a temperature of 550 °C, according to the results. Different concentrations of reactive red 250 (RR250) dye photodegradation was evaluated using different doses of CuCe-ferrite/ TiO2 and TiO2 NPs. Higher efficiency of RR250 photodegradation up to 100% was obtained using CuCe-ferrite/ TiO2. The photodegradation efficiency was confirmed using chemical oxygen demand (COD) test of both treated and untreated samples. The oxidation process was mostly mediated by photogenerated .O2− according to scavenger test results. The catalyst possess higher photodegradation efficiency even after regeneration for ten times. [ABSTRACT FROM AUTHOR]

An effort has been made to develop and synthesize novel CoCr2O4@GeO2@ZnO core–shell nanostructure gas sensor via sol–gel method. The products obtained were analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM), energy dispersive X-ray analysis (EDAX), and Brunaure–Emmet–Teller (BET) analysis. In the present study gas sensing properties of CoCr2O4, CoCr2O4@GeO2, and CoCr2O4@GeO2@ZnO were studied. The thick films of cobalt chromite and core–shell CoCr2O4@GeO2, and CoCr2O4@GeO2@ZnO were prepared by screen printing technique. The sensing efficiency of these films was checked for various gases including CO, CO2, Cl2, H2, NH3, and H2S. Among these metal oxide-based sensing materials, CoCr2O4@GeO2@ZnO shows highest response at 200 °C for H2S is 627.01, as compared CoCr2O4@GeO2 is 524.01. The pure chromite (CoCr2O4) shows NH3 gas response is 513.21 at 250 °C. The gas response, selectivity, thermal stability and recovery time of sensor is also studied. The humidity dependence of the sensor response for CoCr2O4@GeO2@ZnO was investigated within the test chamber at 100 °C. The statistical analysis data for gas detection is also predicted. [ABSTRACT FROM AUTHOR]

Flexural behavior of red deer's (Cervus Elaphus) antler is managed by not only orientation of osteons but also age, number density of fully fledged Cross-Linking Fibers (CLFs) and mineralization. Although crack propagation is affected by all these factors, a possible role of CLFs during the deformation remains rather disguised. The aim of this study was to enlighten the effect of dimensions, micro skeleton and mineral content of CLFs on plastic deformation. Therefore, mechanical properties, microarchitecture and mineralization of fracture sites of deer antlers were investigated using three-point bending tests in 32 specimens followed by high resolution scanning electron microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The bending tests show that maximum bending strength is in the range of 150–177 MPa, and elastic modulus approximates to 5–6 GPa. Furthermore, fracture toughness of the test specimens examined for all branching groups of antlers was 8–9 MPa · m 1 / 2 . Age and the number of branching albeit are main reasons for differentiating microarchitecture and varying mechanical properties. SEM analyses show that a hierarchical architecture from bottom to up exists, in which some feathers and nano-sized fibrils are attached to larger fibrils that brings CLFs altogether. Antlers of adolescent deers are supposed to have shorter and thinner cross-linking fibers than elder ones. Some feathered micro-fibrils were identified across the CLFs connecting osteons. The thickness (270.0–320.0 nm) and length (700 nm) of feathers were strictly proportional to the microfibrils' size (10.0 µm in length and 1.0 µm in thickness). Furthermore, weight percentages of minerals varies along the CLFs that taking root on osteons by a bundle of many smaller fibrils whereas Pb, Cd and Hg have the highest values at the tip of broken CLFs. Such high values of these brittle elements lead to cracked ligament bridging as well. [ABSTRACT FROM AUTHOR]

In this paper, the role of antimony (Sb) as a dopant in single-phase bulk Cu2ZnSnSe4 (CZTSe) has been studied. The sb-doped CZTSe bulk material has been synthesized via facile mechanical dry ball milling method. The structural characterization and phase formation were studied through X-ray diffraction (XRD) and Raman spectroscopy. Particle size and electron diffraction measurements were done using high resolution transmission electron microscopy and selected area electron diffraction. Field emission scanning electron microscope and energy dispersive X-ray spectroscopy analyses have been done to infer morphology and composition. Oxidation state of constituent elements in milled powder was studied by X-ray photoelectron spectroscopy analysis. The results of XRD and Raman results are suggestive that the dry milling is a reliable method for the synthesis of single-phase CZTSe. It is also possible to achieve doping with low concentrations of Sb during the milling process to obtain sb-doped bulk single-phase CZTSe. [ABSTRACT FROM AUTHOR]