Laser beam has been widely used to improve the mechanical properties of the metals. It used for cutting, drilling, hardening, welding……etc. The use of Laser beam has many features in accuracy and speeding in work, also in the treatment of metals locally, and in the places that is hard to reach by traditional ways. In this research a surface treatment was done to medium carbon steel (0.4%C) which is common kind of steel that is used in industry. Pulsing Neodymium -YAG Laser has been used and 1.06 micrometer wave length and 5 msec and the distance is about 30 centimeter between the exit area of the Laser beam from the system and the piece that treated . We are going to check the fatigue resistance for samples that is treated by Laser beam and Scanning Electron Microscope (SEM) and also we made check for the microstructure by using the light microscope and the SEM for the breaking samples. The results of checking showed that there is an improvement in the fatigue resistance after the treatment by the Laser beam. The results of microscope checking showed that the beginning of the failure is from the surface area and there is more than one level of the break.
This study was conducted at the Poultry Research Station, Animal Resources Research Department at the Agricultural Research Department / Ministry of Agriculture - Baghdad Abu Ghraib. To find the effect of adding different proportions of Bay Laurus powder on productive performance and some physiological characteristics of birds during the production stage as Eight Hundreds Female birds of quail were used at the age of 45 days, randomly deployed to 4 treatments with two replicates (100 birds / replicate ) each, and the bay laurel powder was added in the proportions 0.0, 0.5, 1.0, and 1.5% to the diets and for a period of 60 days divided into 4 periods of 15-day .The results indicated si
Background: This study was performed to determine the effect of aging of different types of composite material restorations on: Shear bond strength (SBS) to light cure and no mix chemical cure orthodontic adhesives with sapphire bracket and the debonding failure sites. Materials and methods: One hundred forty four composite disks were made from three different composite resin materials which are: 3M Filtek Z250, 3M filtek Z350 and 3M Valux plus, each group with (48) disks each, then according to the duration of storage each group was subdivided into two equal groups one of them stored for one day and the other was stored for one month, then each group was further subdivided into two equal subgroups with (12) disks each one bonded with ligh
... Show MoreThe current research aims to identify the effect of the learning mastery strategy using interactive learning as a therapeutic method on the achievement of secondary school students in mathematics. To achieve the research objective, the researcher selected second-grade middle school students at Al-Haybah Intermediate School for Boys and determined his research sample, which consisted of (77) students distributed into two sections: Section (A) the experimental group, with (38) students, and Section (B) the control group, with (39) students. The statistical equivalence of the two research sample groups was confirmed in the variables (intelligence test, previous achievement, and previous knowledge test). The researchers chose the par
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Polycyclicacetal was prepared from the reaction of PEG with aldehyde derived from Erythro-ascorbic acid (pentulosono-ɣ-lactone-2,3-enedianisoate).All these compounds were characterized by Thin Layer Chromatography (TLC) and FTIR spectra and aldehyde was also characterized by (U.V-Vis), 1HNMR, 13CNMR, and mass spectra.The inhibitory effect of prepared polymer on the activity of human serum AcetylCholinesterase has been studied in vitro. The polymer showed a remarkable activity at low concentration (4.7x10-3 – 4.7x10-8M).
This study was carried out at the Poultry Research Station belong to state Board of Agricultural Research, Ministry of Agriculture, Abu Ghraib. The duration of this study was from 28 November 2013 to 15 May 2014 to evaluate the effect of supplementation different levels of organic selenium(Se-yeast) and inorganic selenium (Selenium selenite) on some productive performances of broiler breeder and selenium levels in plasma ,egg (yolk,albumin). The study included 336 female broiler breeder and 28 males (Ross 308 and arbor acres), 42 weeks old were randomly distributed to 7 dietary treatments experiment with 2 replicates / treatment (24 females and 2 male birds /replicate). The duration of the experiment was 24 weeks, and treatments were as the
... Show MoreBackground: A recent discoveries used for reconstruction in maxillofacial surgery is the composite bone graft materials. The availability of collagen I matrix make our choice to use this material in surgery .It is biomaterials that its structure could be modified by simple techniques. Studies to find a new materials use for bone reconstruction is to overcome the disadvantages of autogenous bone and the synthetic resorbable bone substitutes.
Objectives: This study was done to evaluate the effect of biphasic calcium phosphate collagen composite (ccpc) on healing of bone defects after oral surgical procedures.
Type of the study: A cross sectional study.
Method: It involved 60 patients, 35 male and 25 female, age (15-
... Show MoreManagement Representations Letter plays a significant role as an evidence to get conclusions the Auditor is looking for. These conclusions could show the professional opinion of auditor over the fairness and integrity of financial statements for many issues and numbers that management claims, Hereby, the research aims at highlighting the importance of Management Representations Letter and the way of using as an evidence with expressing its meaning and means of application in addition to identify the Responsibility of Auditor on that Letter, This research discusses also the effect of Management Representations Letter on the credibility of financial statement and enhancing the credibility of the submitted reports, From other side, in the t
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