The Liquid Phase Deposition of ZnPtBNs: Study on Structural, Morphology, and Their Sheet-Resistant

This paper reports ZnPt bimetallic nanoparticles (ZnPtBNs) synthesis through the liquid phase deposition (LPD) of of Zn(NO3)2.6H2O onto the indium-titanium oxide (ITO) substrates at various concentrations. The Effects of growth solution, the morphology, structural, and sheet resistance were studied. After preparation, the materials were characterized by using field emission electron microscopy (FESEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and Four Point Probe (FPP) measurement by using Keithley 2401 source-meter. By inserting a growth solution into the ITO substrate the ZnPtBNs was successfully in-situ prepared. The synthesized ZnPtBNs exhibited homogeneous, fibrous at the (111) orientation with an average diameter of 100-700 nm. The atomic ratio of Zn:Pt and sheet resistance of ZnPtBNs decreased with the increase of Zn(NO3)2.6H2O concentration. The optimal elemental composition of the sample was at a ratio of Zn:Pt (1:25) obtained at 0.467 mM of Zn(NO3)2.6H2O. It showed the smallest sheet resistance (13.41 ?) which was 38% lower than the ITO sheet resistance (18.44 ?).

Exothermic behaviour of aluminium and graphene as a fuel in Fe2O3 based nanothermite

The main frontier of this research is to study the influence of multi-layer graphene (MLG) and aluminium as a fuel in Al/Fe2O3 and MLG/Fe2O3 nanothermites, fabricated by physical mixing and ultrasonication techniques. To study the structural and energy release properties, prepared samples were characterized by XRD, FESEM, EDS, FTIR, Raman spectroscopy and DSC. The X-ray diffraction (XRD) technique showed that all the phases remain intact during the synthesis. Field emission electron microscopy (FESEM) micrographs displayed the surface morphology of the samples, and besides this, energy dispersive spectroscopy (EDS) was used to check the elemental composition of samples. Raman spectroscopy revealed that the ultrasonication waves did not deteriorate the aromatic structure of graphene sheets. Fourier transform infrared spectroscopy (FTIR) spectra were used to observe the information about various functional groups present in the thermite samples. The exothermic energy released by the thermite reaction in both the samples was investigated by differential scanning calorimetry (DSC) and the observed values of energy release for Al/Fe2O3 and MLG/Fe2O3 are 215 J/g and 1640 J/g.

Green Synthesis and Incorporation of Sericin Silver Nanoclusters into Electrospun Ultrafine Cellulose Acetate Fibers for Anti-Bacterial Applications

Fiber based antibacterial materials have gained an enormous attraction for the researchers in these days. In this study, a novel Sericin Encapsulated Silver Nanoclusters (sericin-AgNCs) were synthesized through single pot and green synthesis route. Subsequently these sericin-AgNCs were incorporated into ultrafine electrospun cellulose acetate (CA) fibers for assessing the antibacterial performance. The physicochemical properties of sericin-AgNCs/CA composite fibers were investigated by transmission electron microscopy (TEM), field emission electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FTIR) and wide X-ray diffraction (XRD). The antibacterial properties of sericin-AgNCs/CA composite fibers against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) were systematically evaluated. The results showed that sericin-AgNCs incorporated in ultrafine CA fibers have played a vital role for antibacterial activity. An amount of 0.17 mg/mL sericin-AgNCs to CA fibers showed more than 90% results and elevated upto >99.9% with 1.7 mg/mL of sericin-AgNCs against E. coli. The study indicated that sericin-AgNCs/CA composite confirms an enhanced antibacterial efficiency, which could be used as a promising antibacterial product.

Compatibilization and Characterization of Polylactide and Biopolyethylene Binary Blends by Non-Reactive and Reactive Compatibilization Approaches

In this study, different compatibilizing agents were used to analyze their influence on immiscible blends of polylactide (PLA) and biobased high-density polyethylene (bioPE) 80/20 (wt/wt). The compatibilizing agents used were polyethylene vinyl acetate (EVA) with a content of 33% of vinyl acetate, polyvinyl alcohol (PVA), and dicumyl peroxide (DPC). The influence of each compatibilizing agent on the mechanical, thermal, and microstructural properties of the PLA-bioPE blend was studied using different microscopic techniques (i.e., field emission electron microscopy (FESEM), transmission electron microscopy (TEM), and atomic force microscopy with PeakForce quantitative nanomechanical mapping (AFM-QNM)). Compatibilized PLA-bioPE blends showed an improvement in the ductile properties, with EVA being the compatibilizer that provided the highest elongation at break and the highest impact-absorbed energy (Charpy test). In addition, it was observed by means of the different microscopic techniques that the typical droplet-like structure is maintained, but the use of compatibilizers decreases the dimensions of the dispersed droplets, leading to improved interfacial adhesion, being more pronounced in the case of the EVA compatibilizer. Furthermore, the incorporation of the compatibilizers caused a very marked decrease in the crystallinity of the immiscible PLA-bioPE blend.

Effect of Temperature on Morphology, Phase Transformations and Thermal Expansions of Coal Fly Ash Cenospheres

Cenospheres are small, hard-shelled hollow spheres with high silica and alumina content. These micron-sized aluminosilicate hollow spheres constitute only a small percentage of the coal fly ash (CFA) obtained from the coal combustion processes. In this study, cenospheres were separated from CFA obtained from a coal-fired power plant located in Kapar, Malaysia. The cenospheres were heated at 1000, 1200 and 1400 °C to study the changes in morphologies, compositions, phase formation and thermal expansion. The sintering temperatures were selected based on the differential scanning calorimetry (DSC) curve results. X-ray diffractometry (XRD), field emission electron microscopy (FESEM), energy dispersive spectroscopy (EDS) as well as thermogravimetry and differential scanning calorimetry analysis (TG–DSC) were used for the characterization study. The study found that the cenospheres have excellent weight stability but are thermally unstable as a result of crystallization and melting. The phase ordering process and devitrification of the amorphous aluminosilicate glass phase at high temperatures lead to the increment and enrichment of the mullite phase in cenospheres. It is suggested that a preheating treatment at 1100 °C could be used to enhance the mechanical properties and thermally stabilize the cenospheres, which make it more suitable for use as a pore-forming agent in ceramics.

Surface Plasmon Resonance Sensor Based on Polypyrrole–Chitosan–BaFe2O4 Nanocomposite Layer to Detect the Sugar

The surface plasmon resonance sensor was used to detect and measure low concentrations of sugar. A polypyrrole–chitosan–BaFe2O4 nanocomposite layer was prepared to improve the surface of the gold layer for the detection of glucose, fructose, and sucrose using the surface plasmon resonance technique. The polypyrrole–chitosan–BaFe2O4 was synthesized using the electrodeposition method in different thicknesses. The functional group, crystal structure, and morphology of the layer were investigated with Fourier transform infrared spectroscopy, X-ray diffraction technique, and field emission electron microscopy. Consequently, the BaFe2O4 was scattered on the surface of the polymer, and the affinity of polypyrrole–chitosan–BaFe2O4 to bond with glucose is higher than that for the other sugars. The sensor limit was 0.005 ppm.

Photocatalytic Performance of CdS/(Pt-TiO2)-Pumice for E. Coli Disinfection in Drinking Water

Photocatalytic removal of E. coli pathogen bacteria existing in drinking water was studied in this paper. CdS/(Pt-TiO2) nanocomposite was produced by depositing Pt/CdS on TiO2 nanoparticles with chemical reduction and hydrothermal method. On the other hand, CdS/(Pt-TiO2)-Pumice was fabricated by immobilizing of titania composite onto pumice with dip coating method to become photocatalysis without causing problem in the separation titania from solution. The Field Emission Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), UV-Vis Diffuse Reflectance Spectroscopy (UV-Vis DRS) were utilized to characterize the photocatalyst samples. Based on the morphology characterization, it was observed that successful deposition of Pt and CdS on TiO2 occurred. Furthermore, decorating Pt/CdS on TiO2 can reduce bandgap energy compare to the bare TiO2 according to the UV-Vis DRS analysis. The treatment of E. coli inactivation with CdS/(Pt-TiO2), CdS/(Pt-TiO2)-pumice and without photocatalyst had performed in the photoreactor that irradiated with mostly visible light in 90 min. The amount of photocatalyst and the contact mechanism between the photocatalyst and bacteria in the water would effects the performance of E-coli photocatalytic disinfection in drinking water

Магнитные нанокомпозиты MgFe-=SUB=-2-=/SUB=-O-=SUB=-4-=/SUB=-/SiO-=SUB=-2-=/SUB=- типа ядро/оболочка для биомедицинских применений: синтез и свойства

Magnetic core/shell (CS) nanocomposites (MNCs) are synthesized using a simple method, in which a magnesium ferrite nanoparticle (MgFe_2O_4) is a core, and an amorphous silicon dioxide (silica SiO_2) layer is a shell. The composition, morphology, and structure of synthesized particles are studied using X-ray diffraction, field emission electron microscopy, transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), scattering electrophoretic photometer, thermogravimetric analysis (TGA), and Mössbauer spectroscopy. It is found that the MgFe_2O_4/SiO_2 MNC has the core/shell structure formed by the Fe‒O–Si chemical bond. After coating with silica, the MgFe_2O_4/SiO_2 MNC saturation magnetization significantly decreases in comparison with MgFe_2O_4 particles without a SiO_2 shell. Spherical particles agglomerated from MgFe_2O_4 nanocrystallites ∼9.6 and ∼11.5 nm in size function as cores coated with SiO_2 shells ∼30 and ∼50 nm thick, respectively. The total size of obtained CS MNCs is ∼200 and 300 nm, respectively. Synthesized CS MgFe_2O_4/SiO_2 MNCs are very promising for biomedical applications, due to the biological compatibility of silicon dioxide, its sizes, and the fact that the Curie temperature is in the region required for hyperthermal therapy, 320 K.

Micro friction stir lap welding of AISI 430 ferritic stainless steel: a study on the mechanical properties, microstructure, texture and magnetic properties

In this study, the effect of friction stir welding of AISI 430 (X6Cr17, material number 1.4016) ferritic stainless steel is examined. Two thin sheets with dimensions of 0.4 × 50 × 200 mm3 are joined in lap configuration. Optical microscopy and field emission electron microscopy were used in order to microstructural evaluations and fracture analysis, respectively. Tensile test and microhardness measurements are employed in order to study the mechanical behaviors of welds. Also, vibrational sample magnetometry (VSM) is employed for characterizing magnetic properties of welded samples. Texture analysis is carried out in order to clarify the change mechanism of magnetic properties in the welded area. The results show that AISI 430 sheets are successfully joined considering both, the appearance of the welding bead and the strength of the welded joint. It is found that by friction stir welding of AISI 430 sheets, texture components with easy axes magnetization have been replaced by texture components with harder magnetization axes. VSM analysis showed that friction stir welding leads to increase in residual induction (Br) and coercivity (Hc). This increase is attributed to the grain refining due the friction stir welding and formation of texture components with harder axes of magnetizations.

Effect of carburizing and annealing processes in improving the Ni/WC–Co adhesion strength

Heat treatment processes have a positive impact in improving the adhesion strength of different interlayer/substrate materials. However, information regarding the effect of these processes in enhancing the adhesion strength of an electroplated nickel interlayer on tungsten carbide substrate for diamond deposition is lacking. In this study, the effect of carburizing and annealing process conditions in enhancing the adhesion strength of the electroplated nickel interlayer was investigated. The heat treatment processes were designed and modeled by the design of experiments technique. The heat-treated specimens were characterized by the field-emission electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction techniques. The adhesion of the interlayer before and after the heat treatment was assessed by the scratch test. The results show that the adhesion of the electroplated nickel interlayer was remarkably improved by both processes. The mathematical models for predicting the adhesion strength of the carburized and annealed nickel interlayer within the specified ranges were developed. The maximum adhesion strength of 30 N was obtained from the nickel interlayer annealed at the highest process condition of temperature and time.