This study aims to determine the effect of x-ray radiation resulting from solar flares in high-frequency radio wave communications through the ionosphere and to study the radio blackout events that occur over Iraq, located within (38,28) latitude, and (38,49) longitude. Using X-ray data during strong X flares and radio wave absorption data across the D ionosphere for 10 years from 2012 to 2021. The study concluded that there were 43 events of x-flare, most of which were during years of high solar activity. All of these flares produced X-rays that caused a radio blackout, R3 and only 13 events affected Iraq.
There are many events which causes nonproductive time (NPT) in the drilling industry. The mostly effective in this NPT is pipe sticking event. A considerable amount of time and resources can be spent in efforts to free a stuck pipe. In addition, Unsuccessful fishing operations results in costly alternatives including side-tracking. The drilling in Khabaz oil field poses many operational challenges among of them stuck pipe , lost circulation, flow of salt water during drilling, and hole caving. Stuck pipe can be considered the quite difficult problem in Khabaz oil field due to associated incidents which lead to NPT activities.
Well Khabaz -34 was selected to study the problem of stuck pipe in this field. An analysis of stuck pipe event
One of the Iraqi geotechnical problems is the presence of gypseous soils covering about (27-36) percentage of Iraq soils containing gypsum between (10-70) ratios. The main reason for soil problematic is the gypsum dissolution when these soils are inundated. However, the soluble gypsum can be leached out of the soil particles, so these problems can be led to cracking, tilting, and collapsing the related soil structure and changing the soil properties. The aim of this work is to investigate the performance of under-reamed piles as a new, improved method to reduce the moisture sensitive and the primary triggering mechanism for the volume reduction of collapsible soil, which is considered as a non-elastic deformation; this was done by c
... Show MoreThe plant Abrus precatorius, which belong to Leguminosae (Fabaceae) family and known as Crab’s eyes, Rosary pea with characteristic red and black seeds. It was used in folk medicine in India, China and East Asian countries for treatment of various diseases. The plant was extracted by '' general method of extraction'' (Harborne, 1973) using 80% aqueous ethanol as a solvent of extraction by soxhlet apparatus. Preliminary qualitative phytochemical screening were performed on the crude ethanolic extract and revealed the presence of alkaloids, flavonoids ,terpenoids and phytosterols in Iraqi Abrus precatorius plant. Three different fractions were obtained from crude extract which are fraction one (chloroform fractio
... Show MoreThis paper proposes feedback linearization control (FBLC) based on function approximation technique (FAT) to regulate the vibrational motion of a smart thin plate considering the effect of axial stretching. The FBLC includes designing a nonlinear control law for the stabilization of the target dynamic system while the closed-loop dynamics are linear with ensured stability. The objective of the FAT is to estimate the cubic nonlinear restoring force vector using the linear parameterization of weighting and orthogonal basis function matrices. Orthogonal Chebyshev polynomials are used as strong approximators for adaptive schemes. The proposed control architecture is applied to a thin plate with a large deflection that stimulates the axial loadi
... Show Morehe development of multidrug resistance in Gram-negative bacteria is a major problem faced antimicrobial therapy and management of infectious diseases. Too many resistance mechanisms were developed since the antimicrobial agents were produced and actually used. The mechanisms involved in antimicrobial agents' resistance are, modifying enzymes, alteration of the target site of antimicrobials and prevention of antimicrobials accumulation inside the bacterial cells. The latest is accomplished by two mechanisms: alteration of outer membrane permeability and efflux pumps. Efflux pumps are either chromosomal or plasmid-encoded although chromosomal encoded efflux pumps are common in Gram-negative bacteria. Resistance nodulation division (RND) efflu
... Show MoreNanofluids (dispersion of nanoparticles in a base fluid) have been suggested as promising agents in subsurface industries including enhanced oil recovery. Nanoparticles can easily pass through small pore throats in reservoirs formations; however, physicochemical interactions between nanoparticles and between nanoparticles and rocks can cause a significant retention of nanoparticles. This study investigated the transport, attach, and retention of silica nanoparticles in core plugs. The hydrophilic silica nanoparticles were injected into limestone core as nanofluid of different nanoparticles size (5 nm, and 20 nm), concentration (0.005 – 0.1 wt% SiO2), and base fluid salinity (0 – 3 wt% NaCl) at different temperatures (23, and 50 °C). D
... Show MoreThe family Pholcidae represented by the species Artema doriae )Thorell, 1881) is recorded in Iraq for the first time.So far, 23 families of spiders have been recorded in Iraq.
In this paper, we add a new family and a description of a species belonging to this family in the checklist of Iraqi spider fauna.
Growth of Penicillium expansum, an ubiquitous mould found in stored fruit globallyt, was significantly restricted by exposure to 48 h cell-free supernatant of two strains of Lactobacillus plantarum (p < 0.001). In addition, the biotransformation of patulin, a toxic secondary metabolite formed by P. expansum, on exposure to L. plantarum cells and cell-free supernatant highlights the potential of this GRAS microbe as a biocontrol agent. Up to 80% of patulin was biotransformed following a 4 h incubation with 1010 cells ml−1 (37 °C) forming E- and Z-ascladiol. The formation of these products was more pronounced at elevated pH and cell density. Exposure to cell free supernatant or sonicated cells resulted in complete patulin biotransformation
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