A theoretical study was done in this work for Fatigue , Fatigue Crack Growth (FCG) and stress factor intensity range for steel . It also includes Generalized Paris Equation and the fulfillment of his equation which promises that there is a relation between parameters C and n . Usig Simple Paris Equation through which we concluded the practical values of C and n and compared them with the theoretical values which have been concluded by Generalized Paris Equation . The value of da/dN and ∆K for every material and sample were concluded and compared with the data which was used in the computer program for the whole of our research . The program is written in Fortran . The theoretical and practical data was drawn with (Graf) program so as to conclude the data mentioned in the research .
One of the challenging issues encountered during drilling operations is the lost circulation. Numerous issues might arise because of losses, such as wasting of time and higher drilling cost. Several types of lost circulation materials have been developed and are being used to limit mud losses and avoid associated issues. Each solution has benefits and drawbacks.
In this study, a core flooding test was performed to study the effectiveness of polyacrylamide (PAM) granular gel on the reduction of the circulation lost. One common type of fracture characteristic is fractures with tips, commonly known as partially open fracture (POF). However, PAM gel therapy in POFs received little attention in prior research. Models of partly open fra
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Density Functional Theory (DFT) calculations were carried out to study the thermal cracking for acenaphthylene molecule to estimate the bond energies for breaking C8b-C5a , C5a-C5 , C5-C4 , and C5-H5 bonds as well as the activation energies. It was found that for C8b-C5a , C5-C4 , and C5-H5 reactions it is often possible to identify one pathway for bond breakage through the singlet or triplet states. The atomic charges , dipole moment and nuclear – nuclear repulsion energy supported the breakage bond .Also, it was found that the activation energy value for C5-H5 bond breakage is lower than that required for C8b-C5a , C5a-C5 , C5-C4 bonds which refer to C5-H5 bond in acenaphthylene molecule are weaker than C8b-C5a , C5a-C5 , C5-C
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God urged to read the Holy Qur’an and to ponder it is commanded, and the Most High said: That they ponder over His verses and that those with insights remember ().
And this book that God Almighty sent down to the heart of His Prophet, peace and blessings be upon him, is as clear as the sun and the moon.
It is a book of guidance and the constitution of a nation that is the best nation brought forth for mankind, and God has taken care of its preservation as He said: We have sent down the Remembrance, and we are its guardians.
This has been chosen for this topic (Luqman's commandments to his son) for what we see today in our time and society from the loss of morals and values and the neglect of parents to their chi
In this research a study of the effect of quality, sequential and directional layers for three types of fibers are:(Kevlar fibers-49 woven roving and E- glass fiber woven roving and random) on the fatigue property using epoxy as matrix. The test specimens were prepared by hand lay-up method the epoxy resin used as a matrix type (Quick mast 105) in prepared material composit . Sinusoidal wave which is formed of variable stress amplitudes at 15 Hz cycles was employed in the fatigue test ( 10 mm )and (15mm) value 0f deflection arrival to numbers of cycle failure limit, by rotary bending method by ( S-N) curves this curves has been determined ( life , limit and fa
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Background: One of the major problems in endodontics is micro-leakage of root canal fillings which might contribute to the failure of endodontic treatment. To avoid this problem, a variety of sealers have been tested. The objective of this, in vitro, study was to evaluate the shear bond strength of four resin based sealers (AH plus, silver free AH26, RealSeal SE and Perma Evolution permanent root canal filling material) to dentin. Materials and Methods: Forty non-carious extracted lower premolars were used. The 2mm of the occlusal surfaces of teeth were sectioned, to expose the dentin surface. The exposed dentin surfaces of teeth were washed with 5ml of 2.5% NaOCl solution followed by 5ml of 17 % EDTA then rinsed by deionized water to remov
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The experiment was carried out in the green house of, Biology Department of ,College of
Education , Ibn Al-Haitham , Baghdad University. For growth season 2008-2009 via planting
seeds of three genotypes of barley cultivars Baraka , Becson and Baraka x Forest ,to study the
effect of different concentrations of NaCl (o , 50 ,100 , 150 , 200 ) mM.L on some
growth parameters such as fresh and dry weight of shoot and elements plants the experiment
carried out by using completely randomized design applied with four replicates . Data were
statistically analyzed by using least significant differenceat0.05probabilitylevel.
The results showed that an increase in NaCl salt concentrations from 0 to 200mM.L
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leads
Dried imported blood worms Chironomus reparius was used to motivate the growth of young carp Cyprinus carpio L ., as fish powder was partial and total replaced by blood worms which is a component of the fodder of the common carp fish. Results have shown that blood worm partial replacement treatment surpasses the imported fish powder. Rates of growth motivation of this treatment have been higher than both the control and total replacement processes. Results have shown significant differences in the weight of the fish in the partial replacement of the fish powder by the blood worms.