The present study considers an influence of WS2 nanoparticles lubricants on physical characteristics of wrought Aluminium alloys. It is investigated parameters-performance relationship via tribological pin-on-disc tests, the pin is made of Aluminium alloys and the disk is made of AISI.1045, and the humidity was 70%. Oils with WS2 nanoparticles and without them reveal the loss rate of wear. In this study, the coefficient of friction (CoF) is reduced from 0.27 to 0.22 and the wear rate decreased from 0.128 x 10-6 Nm-1 to 0.107 x 10-6 Nm-1 at a load of 20 N. All worn surfaces were typically three types in wear mechanisms such as adhesive, abrasive, and oxidative wear. In addition, the use of nanoparticle enhanced the viscosity. This study showed promising results and concluded that the wrought Aluminium alloy to be the superior with WS2 nanoparticles, Furthermore, the wear rate has been reduced of 14% comparison without the use of WS2.
In the present study, we have reported investigations on the effect of simultaneous substitution of Tl at the Hg site in the oxygen deficient HgOδ layer of Hg1-xTlxBa2Ca2Cu3O8+ δ cuprate superconductor. Bulk polycrystalline samples were prepared by the two-step solid state reaction process. It was observed that the grown Hg1-xTlxBa2Ca2Cu3O8+ δ corresponds to the 1223 phase. Electrical resistivity, using four probe technique, is used to find the transition temperature Tc. The highest Tc(0ffset) were 108, 102,113, 118, 125 and 121K for Hg1xTlxBa2Ca2Cu3O8+ δ with x = 0.0, 0.05, 0.10, 0.15, 0.20 and 0.25 respectively. The optimum Tc(off) of ~ 125 K and Tc(onset) ~ 136K was fo
... Show MorePulsed liquid laser ablation is considered a green method for the synthesis of nanostructures because there are no byproducts formed after the ablation. In this paper, a fiber laser of wavelength 1.064 µm, peak power of 1 mJ, pulse duration of 120 ns, and repetition rate of 20 kHz, was used to produce carbon nanostructures including carbon nanospheres and carbon nanorods from the ablation of asphalt in ethanol at ablation speeds of (100, 75, 50, 10 mm/s). The morphology, composition and optical properties of the synthesized samples were studied experimentally using FESEM, HRTEM, EDS, and UV-vis spectrophotometer. Results showed that the band gap energy decreased with decreasing the ablation speed (increasing the ablation time), the mi
... Show MoreFriction stir welding (FSW) process is an emerging solid state joining process in which the material that is being welded does not melt. This process uses a nonconsumable tool to generate frictional heat in the abutting surfaces. The welding parameters such as tool rotational speed, welding speed, axial force, etc., and tool pin profile play a major role in deciding the weld quality. In this investigation an attempt
has been made to understand the effect of tool pin profile and rotation diameter on microstructure and mechanical properties in aluminum alloy (2218-T72). Five different tool pin profiles (straight cylindrical, threaded cylindrical, triangular, square, and threaded cylindrical with flat), with three different rotation
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Stabilization of phenol trapped by agricultural waste: a study of the influence of ambient temperature on the adsorbed phenol
The subgrade soil is the foundation plate form of the roadway; it should sustain its structural characteristics throughout the design life of the roadway with minimal requirements for maintenance. When Gypseous soil is implemented in the construction of subgrade, problems regarding collapsibility and poor structural capacity usually occur when the subgrade came in touch with excess water. Asphalt stabilization could furnish a proper solution to such problems. In this investigation, an attempt has been made to monitor the variations in compressibility characteristics of asphalt stabilized subgrade soil subjected to 30 cycles of (freezing-thawing) and (heating-cooling). Data have been observed after each 10 cycles, and compared with that of r
... Show MoreA one-dimensional hydraulic model was conducted to simulate the flow in Diyala River. The research aims to study the flow capacity along Diyala River and especially concerning on reach of the river within Baqubah City during flood seasons by using HEC-RAS, 5.07 software. Moreover, specifying the hydraulic problems and then the necessary treatments to overcome them were suggested. A 190 km length of the reach of Diyala River was included in this study, starts from Diyala submerged weir to the confluence of Diyala-Tigris River south of Baghdad City. Good agreement resulted between the measured and the simulation results with a determination coefficient (R2) value of 0.84 with Manning Co
The results of the study showed the statistical significant difference (P≥0.05) for each of the relative weight of the yolk and egg whites, the relative weight of the shell and the Hauh unit, which is affected positively by the addition of ground fenugreek seed and Laurels leave to the quail bird's diet. There is also a statistically significant difference positively for each of the percentage of ash, protein and carbohydrates for qualis egg, while there is no significant difference for both the percentage of moisture and fat. The results of the mineral estimation showed an increase in each of the elements of iron, copper and cadmium from the addition of fenugreek and laurels leave, while there was no significant difference for
... Show MoreThis paper presents a research for magnetohydrodynamic (MHD) flow of an incompressible generalized Burgers’ fluid including by an accelerating plate and flowing under the action of pressure gradient. Where the no – slip assumption between the wall and the fluid is no longer valid. The fractional calculus approach is introduced to establish the constitutive relationship of the generalized Burgers’ fluid. By using the discrete Laplace transform of the sequential fractional derivatives, a closed form solutions for the velocity and shear stress are obtained in terms of Fox H- function for the following two problems: (i) flow due to a constant pressure gradient, and (ii) flow due to due to a sinusoidal pressure gradient. The solutions for
... Show MoreLiquid-side mass-transfer coefficients (KLa) were measured in air-suction type fermentors using physical absorption of oxygen. A fermentor of 0. 5 m i.d. was used with a working capacity of 60 liters of liquid. Tap water was used as the liquid phase, and air was used as the gas phase. The bioreactor mixing system consists of shrouded-disk/curved-blade turbine with six evacuated bending blades. The effect of liquid submergence (S) was investigated. Further, the effects of the ratio of the impeller diameter (D) to the tank diameter (T), and the clearance of the impeller from the tank bottom(C) were also studied. The agitation speed (N) was varied in the range of 50-800 rpm. It was found that the value of K
... Show MoreIt is no secret to anyone that the Koran is a speech to people, and how it is not a speech to humans is a home to them and suitable for their understandings, and the people of rhetoric mean great care has never been before in the division of the Koranic discourse, followed by linguists and science of the Koran. After reading the letter, I followed it in the Holy Quran, taking advantage of what was written by former writers in language and interpretation. Thanks to God, I have done what I wanted. Perhaps one of the most important reasons that led me to write my research and optional for this topic; is related to the Koran. So I started to develop the research plan, and divided it as I saw it, I started to pave the way, and then divided it
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