The use of multifunction additives in the lubricant sector has attracted great interest due to their ability to simultaneously improve and add multiple functions. This work describes the preparation and evaluation of over-based magnesium stearate detergent as a multifunction additive by the reaction of stearic acid with carbon dioxide gas in the presence of magnesium oxide nanoparticles and ammonia. The prepared over-based magnesium stearate was evaluated as a multifunction additive through blending it in various concentrations of 1-5 wt/wt% with sixty stock lubricating oils. The American Society for Testing and Materials (ASTM) and the Institute of Petroleum (IP) were used to determine the total base number (TBN), viscosity index (VI), pour point (PP), rust prevention, copper corrosion inhibition, and oxidation stability. The over-based magnesium stearate detergent gave higher values for TBN and detergency efficiency. The blended oil with one percent of the prepared additive showed more rust, oxidation, and corrosion resistance than the standard antioxidant (hindered phenol HP). The VI values of the blended oils showed that the 5 wt/wt% over-based magnesium stearate, which has approximately the same VI values as the blend with 5% of the standard olefin copolymer (OCP), provides better performance.
Gold nanoparticles (Au NPs) have been synthesized via reduction of sodium tetrachloroaurate dihydrate (NaAuCl4.2H2O) with 2-(2-methyl-5-amino -1H-imidazol-1-yl) ethanol (2-MAE) in presence and absence of ascorbic acid as reducing and stabilizing agents. The resulting Au NPs were characterized by UV–Vis spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), FT-IR spectroscopy. The absorption spectra of gold nanoparticles solutions in the uv-visible and near IR regions were studied at different amine concentrations and pH media.
Gold nanoparticles (Au NPs) have been synthesized via reduction of sodium tetrachloroaurate dihydrate (NaAuCl4.2H2O) with 2-(2-methyl-5-amino -1H-imidazol-1-yl) ethanol (2-MAE) in presence and absence of ascorbic acid as reducing and stabilizing agents. The resulting Au NPs were characterized by UV–Vis spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), FT-IR spectroscopy. The absorption spectra of gold nanoparticles solutions in the uv-visible and near IR regions were studied at different amine concentrations and pH media.
Nanomaterials became targeted materials for many important applications due to its huge surface area and quantum confinement effects. In this work TiO2 nanoparticles (30nm) were used as additive to enhance the corrosion protection of steel rebar in artificial concrete solution (Ca(OH)2 (2g), KOH (22.44mg), NaOH (8mg) in 1L of distilled water) against saline environment (3.5%NaCl) at four temperatures; 20, 30, 40, and 50á´¼C. Three different concentrations of TiO2 NPs were used namely; 1, 3, and 5% by weight. The corrosion parameters and pitting probability were followed using Tafel and cyclic polarization plots respectively. Protection enhancement was recorded at all TiO2<
... Show MoreAzo ligand 11-(4-methoxyphenyl azo)-6-oxo-5,6-dihydro-benzo[4,5] imidazo[1,2-c] quinazoline-9-carboixylic acid was derived from 4-methoxyaniline and 6-oxo-5,6-dihydro-benzo[4,5]imidazo[1,2-c]quinazoline-9-carboxylic acid. The presence of azo dye was identified by elemental analysis and spectroscopic methods (FT-IR and UV-Vis). The compounds formed have been identified by using atomic absorption in flame, FT.IR, UV-Vis spectrometry magnetic susceptibility and conductivity. In order to evaluate the antibacterial efficiency of ligand and its complexes used in this study three species of bacteria were also examined. Ligand and its complexes showed good bacterial efficiencies. From the obtained data, an octahedral geometry was proposed for all p
... Show MoreIraq's oil industry has been passed in different periods , began with domination of Western companies to invest in Iraqi oil at twenties of the last century , through the process of nationalization of the shares of those companies , beginning of the seventies , and ending with the new policies adopted by the government recently, which was contracting with international companies to develop the oil industry , because of what the outcome of the oil industry from a decline in artistic and physical ability as a result to the conditions of war and embargo imposed on Iraq before 2003.
The Iraqi government has introduced licensing of a contract to
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The economic and financial crises in the world economy series led to increased awareness of the importance of the internal control system, because it is one of the main pillars of any economic unit, as it works to verify the application of policies, regulations and laws and verification of asset protection from theft and embezzlement procedures, it is also working on trust accounting information imparted through the validation of accounting information, analyze and detect the misleading.
The existence the internal control system a factor in many of the accounting practices that limit the ability of the administration to produce misleading financial reporting
The
... Show MoreBroadband satellite is playing a main role in provision global coverage and onboard processing ability over IP networks to assess user applications. In order to lower the cost, get better security, solve IPv4 addressing limitation, expand the expected advantages of modern routing and mobility characteristics; the next-generation satellite systems ought to support IPv6 and seamlessly incorporate with terrestrial networks including wireless local loops. Satellite communication links have a number of limitations compared to terrestrial communications networks such as large delay and high header overhead for IPv6 consumes the bandwidth and causes lower transmission effectiveness; however, the quality of service (QoS) (such as delay, jitter,
... Show MoreTen new thiourea derivatives 1-10 were prepared in this work using a two-step process that involved reacting 4-methoxybenzoyl chloride with KSCN to afford 4-methoxybenzoyl isothiocyanate. This was followed by reaction with various amines (primary amines, secondary amines, and diamines) to give the aforementioned title products 1-10. These products were characterized by FT-IR, 1H NMR and 13C NMR spectroscopy. Using the DPPH scavenging method, the antioxidant activity of thiourea products was investigated, and derivative 8 had the greatest antioxidant activity in comparison to the other derivatives. Moreover, molecular dockin
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