The Surface Structure and Thermal Properties of Novel Polymer Composite Films Based on Partially Phosphorylated Poly(vinyl alcohol) with Aluminum Phosphate

Partially phosphorylated polyvinyl alcohol (PPVA) with aluminum phosphate (ALPO4) composites was synthesized by solution casting technique to produce (PPVA)100-y-(ALPO4)y (y = 0, 1, and 2). The surface structure and thermal properties of the films were characterized using Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis (TGA). The results showed that the films have higher thermal stability with strong bonding between PPVA and ALPO4

Physico-chemical studies of cuprous oxide (Cu2O) nanoparticlescoated on amorphous carbon nanotubes ( -CNTs)

Amorphous carbon nanotubes ( -CNTs) were synthesized by a chemical reaction between ferroceneand ammonium chloride at a temperature (∼250◦C) in an air furnace. As- synthesized -CNTs werepurified with deionized water and hydrochloric acid. A purified -CNTs were hybridized with cuprousoxide nanoparticles (Cu2O) through a simple chemical process. Morphology of the samples was analyzedwith field emission scanning electron microscope (FESEM) and transmission electron microscopy (TEM).Fourier transform infrared (FTIR) spectra showed the attachment of acidic functional groups onto thesurface of -CNTs and the formation of hybridized -CNTs-Cu2O. Raman spectra reveal the amorphousnature of the carbon. X-ray diffraction (XRD) pattern confirmed the amorphous phase of the carbon andthe formation of Cu2O crystalline phase. The coating of Cu2O was confirmed by FESEM, TEM, and XRD.Optical absorption of the samples has also been investigated and the quantum confinement effect wasillustrated in the absorption spectra

Truncated and Spheroidal Ag Nanoparticles: A Matter of Size Transformation

The ordered arrays of anisotropic mesostructure metal nanoparticle (diameter size in the range of 15 to 200 nm) characteristics are indeed influenced by the combined effect of packing constraints and inter-particle interactions, that is, the two morphological factors that strongly influence the creation of the particles’ shape. In this work, we studied on how the degree of truncation of Ag nanoparticles authorised the mesostructured morphologies and particle orientation preferences within the mesosparticle arrays. The Ag represented the best and most versatile candidate and known for its highest electrical conductivities among other transition metals in periodic table. The interest is motivated by the need to understand the inevitable morphological transformation from mesoscopic to microscopic states evolve within the scope of progressive aggregation of atomic constituents of Ag system. The grazing information obtained from HR-TEM shows that Ag mesosparticles of highly truncated flake are assembled in fcc-type mesostructure, similar to the arrays formed by microscopic quasi-spherical structure, but with significantly reduced packing density and different growth orientations. The detailed information on the size and microstructure transformation have been gathered by fast Fourier transform (FFT) of HR-TEM images, allowing us to figure out the role of Ag defects that anchored the variation in crystallite growth of different mean diameter size particles. The influences on the details of the nanostructures have to be deeply understood to promote practical applications for such outstanding Ag material

An experimental study of the elastic properties of dragonfly-like flapping wings for use in Biomimetic Micro Air Vehicles (BMAV)

This article studies the elastic properties of several biomimetic micro air vehicle (BMAV) wings that are based on a dragonfly wing. BMAVs are a new class of unmanned micro-sized air vehicles that mimic the flapping wing motion of flying biological organisms (e.g., insects, birds, and bats). Three structurally identical wings were fabricated using different materials: acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), and acrylic. Simplified wing frame structures were fabricated from these materials and then a nanocomposite film was adhered to them which mimics the membrane of an actual dragonfly. These wings were then attached to an electromagnetic actuator and passively flapped at frequencies of 10–250 Hz. A three-dimensional high frame rate imaging system was used to capture the flapping motions of these wings at a resolution of 320 pixels × 240 pixels and 35000 frames per second. The maximum bending angle, maximum wing tip deflection, maximum wing tip twist angle, and wing tip twist speed of each wing were measured and compared to each other and the actual dragonfly wing. The results show that the ABS wing has considerable flexibility in the chordwise direction, whereas the PLA and acrylic wings show better conformity to an actual dragonfly wing in the spanwise direction. Past studies have shown that the aerodynamic performance of a BMAV flapping wing is enhanced if its chordwise flexibility is increased and its spanwise flexibility is reduced. Therefore, the ABS wing (fabricated using a 3D printer) shows the most promising results for future applications

Impact of TiO2 nanotubes’ morphology on the photocatalytic degradation of simazine pollutant

There are various approaches to enhancing the catalytic properties of TiO2, including modifying its morphology by altering the surface reactivity and surface area of the catalyst. In this study, the primary aim is to enhance the photocatalytic activity by changing the TiO2 nanotubes’ architecture. The highly ordered infrastructure is favorable for a better charge carrier transfer. It is well known that anodization affects TiO2 nanotubes’ structure by increasing the anodization duration which in turn influence the photocatalytic activity. The characterizations were conducted by FE-SEM (fiend emission scanning electron microscopy), XRD (X-ray diffraction), RAMAN (Raman spectroscopy), EDX (Energy dispersive X-ray spectroscopy), UV-Vis (Ultraviolet visible spectroscopy) and LCMS/MS/MS (liquid chromatography mass spectroscopy). We found that the morphological structure is affected by the anodization duration according to FE-SEM. The photocatalytic degradation shows a photodegradation rate of k = 0.0104 mi

TiO2 nanotubes supported Cu nanoparticles for improving photocatalytic degradation of simazine under UV illumination

Nano size Copper (Cu) incorporated TiO2 nanotubes was successfully synthesized via the anodic oxidation technique in ethylene glycol (EG) containing 0.5 wt % NH4F and 1.6 wt % KOH for the photocatalytic degradation of Simazine (2-chloro-4, 6-diethylamino-1,3,5-triazine) under Ultraviolet (UV) illumination. In the present study, the influence of different loading Cu concentrations on the formation of Cu-TiO2 nanotubes film towards the photocatalytic degradation of Simazine is reported. Based on our study, it was found that the optimum Cu loading concentration was about 0.45 wt % on TiO2 nanotubes film for approximately 64% photocatalytic degradation of Simazine after 4 h under UV illumination. This finding was mainly attributed to the uniform surface covering of the Cu loaded TiO2NTs which acted as electron traps, preventing the recombination of electron hole pairs, eventually leading to higher photocatalytic activity of our photocatalyst in degrading the targeted organic pollutant, Simazine. Moreover, an increased kinetic rate of the degradation to 0.0135 h−1 was observed in the presence of Cu in TiO2NTs

Analysis of photocurrent responses of anodized TiO2 Nanotubes synthesized from different organic electrolytes

Self-organized titanium dioxide (TiO2) nanotubes (NTs) arrays were successfully fabricated via electrochemical anodization of titanium (Ti) foil in an organic electrolyte containing 5wt% of fluoride content. The present work compares two different organic electrolytes (glycerol and ethylene glycol) for the growth of self-organized TiO2 nanotubes by using anodic oxidation strategy. The resultant TiO2 NTs were then subjected to thermal annealing for manipulating the crystalline structure. The SEM images indicated changes in surface morphology of the TiO2 NTs in different electrolytes. It was found that the NT’s dimensional was 56.00nm based on the SEM analyses. Both samples exhibited good photocurrent response; however, TiO2 NTs synthesized in ethylene glycol electrolyte showed promising photocurrent response of 0.385 mA

Optimization of Cobalt Nanoparticles for Biogas Enhancement from Green Algae Using Response Surface Methodology

Organic matter may be converted to energy through various methods, but the most preferable one is the Anaerobic Digestion (AD), specifically for biogas production. In sustainable bioenergy production, it can undoubtedly be called one of the most widely used methods from the various feedstock. Over the past years, algae waste has become an increasingly acute environmental problem but luckily it can be used as feedstock to produce bioenergy. In order to improve the energy productivity of green algae, this study is focused on the introduction of cobalt (Co) nanoparticles (NPs) in the AD process. The concentration of Co NPs was optimized using response surface methodology (RSM). Mesophilic temperature range (25–45 °C), initial pH (5–9) and Co NPs dosage (0.5–2 mg/L) were selected as the independent variables for RSM. The results indicated that at optimized values (Co NPs concentration = 1 mg/L, initial pH = 7, and digestion temperature = 35 °C) produced the highest biogas yield of 298 ml. An experiment was carried out at optimized conditions to explore the effect on biogas production. The results showed that Co NPs had a positive influence on biogas yield. The low concentrations achieved higher biogas production as compared to higher ones. A maximum biogas yield of 678 mL is achieved by Co NPs (1 mg/L). AD performance was further evaluated by the modified Gompertz model. Different kinetic parameters were calculated. The values of the performance indicators confirmed that the mathematical model fitted well with experimental data