Journal of Applied Sciences and Nanotechnology

The depletion of natural resources and the negative impact of oil on the environment have sparked interest in biodiesel as an alternative source of energy. Indigenous vegetable oils have the potential to be used as biodiesel feedstocks. Transesterification of vegetable oils produces biodiesel, which is regulated by numerous inputs factors, such as catalyst dosage, temperature, speed, and time while the density and specific gravity are outputs. Sweet almond (prunusamygdalus dulcis) and jatropha (jatropha curcas) seed oils were used to optimize conditions for the transesterification processes using the response surface methodology (RSM). The experimental matrix at different sodium hydroxide doses (0.3 – 1.5 wt %), intensity (500 – 1000 rpm), and time (20 – 60 min) in the presence of fixed molar ratio, and temperature were designed to optimize the biodiesel output variables (yield, specific gravity, and density).The analysis of variance (ANOVA) showed results for refined sweet almond biodiesel (RSAB) at catalyst (0.554 wt %), speed (750 rpm), time (40 min), giving the optimization solution with the specific gravity (0.995 g/cm3), density (1.230 g/cm3) with the yield of 83.304% for RSAB. Whereas the RJB had the optimum catalyst of (0.3 wt %,), speed (500 rpm), time (44.1 min), with the specific gravity (0.964 g/cm3), density (0.884 g/cm3), and the biodiesel yield of 96.4%. The estimated biodiesel yields vary by 13.096% under these reaction conditions. According to ANOVA statistics, the catalyst dose has a substantial effect on biodiesel yields, and these biodiesels could be employed as an environmentally friendly alternative to diesel.

In this work, it was evaluated the wear resistance, hardness, and surface roughness values of resin-based composites that applied in dentistry as restorative materials. The resin composites were made from six types of resin matrixes (A, B, C, D, E, and F) and each one of them has contained different types and ratios of monomers as well as the inorganic nano-fillers (SiO2, ZrO2, HA, and Al2O3). For each test, thirty specimens were prepared, which were classified into six groups depending on the types of the resin matrix and fillers used in the composites. The results prove that the nanocomposites that have the lowest rate of wear were the group E which was derived from the resin matrix of the group E that has monomers are (BIS-GMA, meth acrylamide, methacrylic acid, and 1-6 hexanediol methacrylate) with values range from 8.11 to 6.11 mm3/mm depending on the filler type material. All prepared composites resin materials (A to F) showed an increase in their hardness values as regards the reference, group D showed the highest hardness value followed by group B while group C was the lowest. The highest mean roughness was shown in groups A and F with 0.82 and 0.79 μm respectively, while the smoother surfaces among all groups were groups B and D which had significantly fewer roughness values of 0.16 and 0.19 μm respectively.

Attapulgite clay is a hydrated magnesium aluminum silicate mineral. Attapulgite clay stone in the Bahr al-Najaf region contains calcite and quartz minerals (43.4%. and 13.9% by weight), respectively. This work is devoted to develop the attapulgite clay found in Bahr Al-Najaf to be suitable for oil wells drilling. The goal of this project is to develop attapulgite mud that meets the American Petroleum Institute (API) for the application of oil well drilling mud in Bahr Al-Najaf. To achieve this objective, unwanted materials (calcite and quartz particles greater than 75 µm in diameter) should be removed and the attapulgite rods dispersed. To make attapulgite mud appropriate for oil well drilling mud. Wet sieving was used to remediate Iraqi attapulgite mud in this study. XRD and SEM tests were done to determine the metals and shape of the prepared Nano MgO to improve the rheological properties. The rheological parameters of attapulgite were measured using an ofite viscometer. Nano MgO was added to attapulgite in three proportions (0.02, 0.05, and 0.08) gm wt. Magnesium oxide showed a great contribution to apparent viscosity and plastic viscosity by 16% of attapulgite aqueous suspensions. The higher viscosity will provide better cuttings carrying capability during drilling fluid circulation especial at low velocity.

Manufacture of an environmental polluting gas sensor with improved properties by controlling the preparation conditions of the photo-electrochemical etching technique (PECE). The amount of porosity, the diameter of the pores, and the thickness of the prepared layer of porous silicon (Psi) can be controlled by changing one or all of these conditions. In this paper, n-type Si with a crystalline orientation (100) was used, whereby PSi was prepared with the use of a red diode laser with a wavelength of 650 nm, using different radiation intensity, and with the constancy of etching time and current density. Through the results obtained, it was noted that: the porosity increases significantly up to 75% as well as the thickness of the PSi layer up to 1.45 µm with the increase in the intensity of the laser beam. Also, examining the morphology of the surface samples by field emission scanning electron microscope (FE-SEM) besides, the average pore diameters of the prepared samples were calculated. It is clear that the intensity of the laser beam used in the irradiation process is one of the important factors in determining the properties of the prepared PSi. PSi samples have been tested by FTIR to investigate chemical bonds on surfaces such as, (Si-Si, Si-H, Si-H2, Si-O-Si, Si-O-Si, Si-H, Si-O-Si). Samples tested as gas sensors and noticed that an increase in the sensing current to 5.3 µA has appeared with the increase of porosity value where methanol gas is used as background.

Natural gas has recently drawn considerable attention due to its low emissions upon combustion. Pipeline transmission of natural gas is costly and always encounters different obstacles. Therefore, an effective industrial alternative for the storage and transmission of natural gas is needed. Hydrates, also known as solidified natural gas, have been proven to be a more feasible replacement compared to pipeline transmission, CNG, or LNG. Scientists have introduced promoters to shorten the induction time, increase the storage capacity, and improve the stability of hydrates. Nanostructure materials have demonstrated promising promotion results, suggesting a bright future and a critical step in the industrialization of this technology. Researchers have mainly used pure methane, which is the main component of natural gas, to form hydrates. In this article, the fundamentals of the selection of a nanopromoter, the hydrate formation process, and related calculations are demonstrated. Finally, recent results have been brought together to provide an overview of advances towards the use of nanostructure promoters to tune hydrates for future industrial processes.

The excessive use of plastics in the last years is the challenge that has arisen in managing plastic wastes to avoid dangerous effects. Polyvinyl chloride is part of these wastes. It can be utilized to produce fuel-like petroleum fractions depending on pyrolysis, which is the thermal decomposition of plastics in the absence of oxygen. This work aims to reduce environmental pollution and reuse plastic waste as an alternative fuel source. A comparison of the thermal and catalytic processes under the optimum temperature 450 oC, pressure 20 bar, and residence time 1hour in a semi-batch reactor with and without adding Pt/Al2O3 and NiMo/Al2O3 catalysts. Thermo-gravimetric analysis (TGA) analysis was made for PVC. Catalysts were characterized by X-RAY diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). The liquid and gas products were analyzed by (GC/MS) to evaluate the quality of products. In the hydro-cracking reaction, most gas products were produced using NiMo/Al2O3 catalyst, about 62.29 wt%. The aromatic and saturated-aliphatic in the liquid using NiMo/Al2O3 catalysts were 21.07 and 72.81 wt%. The aromatics and saturated aliphatic in the liquid product using thermal non-catalytic and Pt/Al2O3 catalysts were 23.83 wt% & 63.52 wt% and 21.88 wt% & 64.01, respectively. The ratio of gasoline range components is the highest in the hydrocracking process on NiMo/Al2O3 catalysts. Using catalytic-hydrocracking on Pt/Al2O3 gives the highest diesel range component. It was confirmed that the generated undesirable product seems was very few in the hydrocracking reactions compared to the thermal cracking reactions.

Denture base poly (methyl methacrylate (PMMA) resin is one of the most frequently used materials in denture base synthesis, but due to its poor mechanical properties, PMMA can be considered a medium for the attachment and growth of a variety of pathogenic bacteria and fungi, particularly due to PMMA's pores and rough surface. The porosity percentage and surface roughness of the PMMA resin sample was lowered in this study, which resulted in a reduction in microorganisms' surface adhesion by varying the ratios of additives such as zinc oxide (ZnO) and tri-calcium phosphate (TCP) nanoparticles with (1, 2, 3, and 10% wt percent) for each additive separately, and 3% as a combination of ZnO and TCP nanoparticles in an equal ratio. Additionally, mechanical features such as surface hardness are developed, which is a critical attribute for polishing and easy finishing, as well as offering great scratch resistance during denture base cleaning. These results indicated that when compared to the other groups, PMMA (ZnO wt. 1%) and TCP-wt. 1%) reinforced composite resins demonstrated the best optimum properties. Additionally, it was discovered that adding 1% of NPs improved the mechanical qualities, which benefited the biological properties by reducing bacterial adherence to the PMMA composite resin.

In this study, using potassium polyacrylate (KPA), polyvinylalcohol (PVA), and zinc chloride as cross-linking agents, successfully synthesized novel superabsorbent polymers. Different weight ratios of KPA and PVA were used to prepare the polymers using polymerization solution. So, polymers with different weight ratios made from PVA and KPA. Superabsorbent polymers (SAPs) were produced using a simple approach at ambient temperature. By comparing absorption peaks, Fourier transform infrared spectroscopy (FTIR) and UV analysis were utilized to investigate the molecular interactions. The morphology of superabsorbent polymers was investigated by scanning electron microscopy (SEM). According to FT-IR, UV, and SEM results, the superabsorbent polymers (Zn-KPA and Zn-PVA) were prepared successfully. A comparison of Zn-KPA and Zn-PVA SAPs was conducted. The effects of cross-linking on water absorption were investigated. The Zn-PVA superabsorbent polymer has a maximum swelling capacity of 407%, while the swelling ratio of the Zn-KPA was 304%. Thus, these prepared superabsorbent polymers could be used for agricultural applications such as water storage. With increasing zinc chloride content and time, superabsorbent polymers’ swelling capacity has considerably improved.

Using a chemical spray technique, an n-type WO3 polycrystalline thin film was prepared with optimizing parameters (molarity concentration of 80 mM and a substrate temperature of 350 °C). Study the physical properties of WO3 thin film via UV-Visible spectroscopy, XRD, Field Emission-Scanning Electron Microscope, Energy Dispersive X-ray Spectroscopy, Atomic Force Microscopy, and current-voltage. Tungsten oxide was deposited on glass surfaces at different molarities ranging from 50–90mM. In the UV-Visible spectrum of the WO3 thin film, it was found that the transmittance, reflectivity, and energy gap decreased (78%–53%), (9.63%–5.02%), and (3.40eV–2.63 eV), respectively. The X-ray diffraction of the WO3 film at the optimized was poly-crystalline and had a monoclinic phase, and the preferred orientation (hkl) was 200 at 2 = 24.19. From the image FESEM and EDX, it was found that it has a multi-fibrous network. The average diameter of the fiber is 266 nm, and the ratio of tungsten to oxygen (W/O) is 2.6, with a stoichiometric of 68.6% at the 80 mM concentration. The Atomic Force Microscopy shows that the WO3 thin layer has a nanostructure. The average surface roughness was 5.3 nm, and the Root Mean Square was 8.6 nm. The WO3 film had the lowest resistivity value of 2.393 × 108 cm, and the activation energy was 0.298 eV, among the parameter of the current voltage at substrate temperature and concentration optimum.

Nowadays, sustainable energies can be found by thermal and catalytic pyrolysis of plastic waste. This study uses high-density polyethylene (HDPE), low-density polyethylene (LDPE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) to investigate thermal and catalytic pyrolysis using a stainless-steel semi-batch reactor at different conditions: Temperatures (350 - 500°C) and residence times (60, 90, and 120 min). The catalysts were undergone to different characterization techniques such as EDX, SEM, and BET that revealed the PR.9 catalyst consists of Cobalt, Molybdenum, and Platinum loaded on Al2O3. Whereas, the chemical compositions of Platinum RG-412 catalyst contain Chlorine and Platinum. The SEM analysis showed that the PR.9 catalyst is more active than RG-412 for the degradation of plastics. In addition, the properties of the liquid products like density, API, and viscosity were studied. As a result, the properties of the liquid produced by the plastic pyrolysis were similar that those produced from the petroleum refineries. The API findings declared that almost all of the liquids produced were light products, which contain mainly diesel oil, gas oil, kerosene, and gasoline.

In this work, a simulation analysis of a commercial magnetron sputtering source was performed using the finite element method Particle-in-Cell/Monte Carlo Collision (PIC/MCC) to optimize the configuration of the Zn-C mosaic target. The magnetic field distribution was solved in a two-dimensional cylindrical coordinate system, and particles such as electrons, atoms, and charged ions of argon, zinc, and carbon were tracked in a DC magnetron sputtering system. The sputtering yield profile and particle flux for the eroded target were studied considering the ion and electron density distributions. The maximum sputtering flux of zinc and carbon was 1.9751021 m-2.s-1 and 3.71018 m-2.s-1 respectively. The erosion position of a target was predicted based on the maximum power density distribution at the surface of the target. The accuracy of the simulation was checked by comparing it with the measurement of the target eroded after several hours of sputtering. However, as for the Zn-C mosaic target, the racetrack was identical to the analysis predicted by the numerical simulation process. The results of this work can be used as a guide for designing mosaic targets and optimizing their use for fabricating nanohybrid thin film structures.