The work reported in this study focusing on the abrasive wear behavior for three types of pipes used in oil industries (Carbone steel, Alloy steel and Stainless steel) using a wear apparatus for dry and wet tests, manufactured according to ASTM G65. Silica sand with
hardness (1000-1100) HV was used as abrasive material. The abrasive wear of these pipes has been measured experimentally by measuring the wear rate for each case under different sliding speeds, applied loads, and sand conditions (dry or wet). All tests have been conducted using sand of particle size (200-425) µm, ambient temperature of 34.5 °C and humidity 22% (Lab conditions).
The results show that the material loss due to abrasive wear increased monotonically with
The rheological behavior among factors that are present in Stokes law can be used to control the stability of the colloidal dispersion system. The felodipine lipid polymer hybrid nanocarriers (LPHNs) is an interesting colloidal dispersion system that is used for rheological characteristic analysis. The LPHNs compose of polymeric components and lipids. This research aims to prepare oral felodipine LPHNs to investigate the effect of independent variables on the rheological behavior of the nanosystem. The microwave-based technique was used to prepare felodipine LPHNs (H1-H9) successfully. All the formulations enter the characterization process for particle size and PDI to ascertain the colloidal properties of the prepared nanosystem t
... Show MoreA group of amine derivatives [4-aminobenzenesulfonamide derivatives, 2-aminopyridine and 2-aminothiazole] incorporated to α-carbon of diclofenac a well known non-steroidal anti-inflammatory drug (NSAID) to increase bulkiness were designed and synthesized for evaluation as a potential anti-inflammatory agents with expected COX-2 selectivity. In vivo acute anti-inflammatory activity of the selected final compounds (9, 12 and 13) was evaluated in rats using egg-white induced edema model of inflammation in a dose equivalent to (3 mg/Kg) of diclofenac sodium. All tested compounds produced a significant reduction in paw edema with respect to the effect of propylene glycol 50
... Show MoreTill now, isatin derivatives have received a lot of interest in organic and medicinal chemistry due to their significant biological and pharmacological activities. Schiff’s and Mannich bases of isatins are an effective group of heterocyclic derivatives that play a significant role in medicinal chemistry as antimicrobial agents. In light of these facts, new Schiff bases and Mannich bases of isatin were synthesized. The monomer Mannich bases; 3(a-e) have been synthesized by reacting isatin with different secondary amines, piperidine, morpholine, and pyrrolidine, dimethylamine, diphenylamine, separately, and formaldehyde, while the dimer (5) formed by using piperazine and formaldehyde which then react separately with Phenylhydrazine
... Show MoreThis paper presents a newly developed method with new algorithms to find the numerical solution of nth-order state-space equations (SSE) of linear continuous-time control system by using block method. The algorithms have been written in Matlab language. The state-space equation is the modern representation to the analysis of continuous-time system. It was treated numerically to the single-input-single-output (SISO) systems as well as multiple-input-multiple-output (MIMO) systems by using fourth-order-six-steps block method. We show that it is possible to find the output values of the state-space method using block method. Comparison between the numerical and exact results has been given for some numerical examples for solving different type
... Show MoreFlexible joint robot (FJR) manipulators can offer many attractive features over rigid manipulators, including light weight, safe operation, and high power efficiency. However, the tracking control of the FJR is challenging due to its inherent problems, such as underactuation, coupling, nonlinearities, uncertainties, and unknown external disturbances. In this article, a terminal sliding mode control (TSMC) is proposed for the FJR system to guarantee the finite-time convergence of the systems output, and to achieve the total robustness against the lumped disturbance and estimation error. By using two coordinate transformations, the FJR dynamics is turned into a canonical form. A cascaded finite-time sliding mode observer (CFTSMO) is construct
... Show MoreABSTRACT Background: Neuropilin 1(NRP1) is considered a novel non - tyrosine kinase co- receptor for the vascular endothelial growth factors (VEGF). First discovered on migrating neurons. NRP1is suggested to be up-regulated in cells of different types of cancer and implicated with advanced disease. The aim of this study was to investigate the variation in expression of NRP1 in oral, laryngeal and skin squamous cell carcinoma. Materials and methods: Tissue sections from 120 formalin fixed- paraffin embedded blocks histopathologically diagnosed as oral, laryngeal and skin SCC (40 blocks for each),immunohistohemically stained in immunoperoxidase method with monoclonal antibodies to NRP1, the localization of expression was examined and the res
... Show MoreThe present paper includes a study of color variation in Iraqi Collared dove Streptopelia decaocto. Three different populations have been recognized: the southern population which belongs to the Indian race, the northern population to the Eurasian race; the dark and light color variation occurs in the Baghdad population because of hybridisation between the two races, found infected with two cestodes, Raillietina echinobothrida found in most of our specimens, while the dark face found beside R. echinobothrida infected with Idiogenes sp. getting it probably from vertebrate sources. We believe that most of the Baghdad population was intermediate between north and south races.
... Show MoreIn this research we solved numerically Boltzmann transport equation in order to calculate the transport parameters, such as, drift velocity, W, D/? (ratio of diffusion coefficient to the mobility) and momentum transfer collision frequency ?m, for purpose of determination of magnetic drift velocity WM and magnetic deflection coefficient ? for low energy electrons, that moves in the electric field E, crossed with magnetic field B, i.e; E×B, in the nitrogen, Argon, Helium and it's gases mixtures as a function of: E/N (ratio of electric field strength to the number density of gas), E/P300 (ratio of electric field strength to the gas pressure) and D/? which covered a different ranges for E/P300 at temperatures 300°k (Kelvin). The results show
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