In this study, Laser Shock Peening (LSP) effect on the polymeric composite materials has been investigated experimentally. Polymeric composite materials are widely used because they are easy to fabricate and have many attractive features. Unsaturated polyester resin as a matrix was selected and Aluminum powder with micro particles as a reinforcement material was used with different volume fraction (2.5%, 5% and 7.5%). Hand lay-up process was used for preparation the composites. Fatigue test with constant amplitude with stress ratio (R =-1) was carried out before and after LSP process with two levels of energy (1Joule and 2Joule). The result showed an increase in the endurance strength of 25.448% at 7.5% volume fraction when peened is 1J laser energy. Also, the ultimate strength and Young’s modulus were increased by 6.474% and 10.588% respectively after LSP with the same laser energy. On the other hand, composites with (2.5% and 5%) volume fraction manifested a reduction in the mechanical and fatigue strength especially when treated by 2J laser energy.
Thin films were prepared from poly Berrol way Ketrrukemaaih pole of platinum concentrations both Albaarol and salt in the electrolytic Alastontrel using positive effort of 7 volts on the pole and the electrical wiring of the membrane record
Cervical ectropion is considered to be a physiologic condition caused by columnar epithelium migration from the cervical canal into the vaginal portion of the cervix and usually there is no treatement for clinically asymptomatic cervical ectropion . Treatment can be achieved by thermal cauterization (Electrocautery), Cryosurgery or laser vaporization. Aim of the study: To study the effectiveness of CO2 laser (10600nm) in treatment of symptomatic cervical ectropion . Setting: The study was carried out at Laser Medicine Research Clinic at the Institute of Laser for Postgraduate Studies, University of Baghdad between the first of August 2013 to the end of October 2013. Patients and Methods: Ten female Patients with age range between 25-48 y
... Show MoreA numerical method (F.E.)was derived for incompressible viscoelastic materials, the aging and
environmental phenomena especially the temperature effect was considered in this method. A
treatment of incompressibility was made for all permissible values of poisons ratio. A
mechanical model represents the incompressible viscoelastic materials and so the properties can
be derived using the Laplace transformations technique .A comparison was made with the other
methods interested with viscoelastic materials by applying the method on a cylinder of viscoelastic material surrounding by a steel casing and subjected to a constant internal pressure, as well as a comparison with another viscoelastic method and for Asphalt Concrete pro
this study aimed to study the effect of Cordia myxa extract on the growth and activities of the following types of bacteria : Escherichia coli , Pseudomonas aeruginosa, Proteus Spp., Klebsiella pneumoniae , Staphylococcus aureus, Streptococcus pyogenes , Bacillus subtilus, and the yeast Candida albicans .the results showed an inhibitory effect of the methanol extract on both the growth and activity of the tested microbes .this was reflected by the minimum inhibitory concentration ( MIC ) of different type of bacteria and the yeast.
Larval instar duration of the house fly Musca domesticais influenced by the application of GHA and precocine. Topical use of ug / ul of JHA KID 183 prolonge Juvenile period compared to the control. On the contrary, application of ug / ul of precocine decreased it. Application of both substances has no effect. The emergence inhibitors were also influenced by such treatments. It reached 52.39% by the use of JHA, (-14.28%) by the use of precocine.
In this work we fabrication holographic optical element diffraction grating thickness 40?m and mirror90?m by using dichromated gelatin,to perform that we have to use the Nd-yaG laser doubling frequency of wavelenght (532)nm and its powers of (80)mWatt.we have studyed the thickness and concentration dichromat effect in mirror reflaction ,effect of angle of reconstruction beam in band width and diffraction efficiency ,study effect gelatin hardener of the diffraction efficiency.
Three new polyphosphates were synthesized in good yields by reacting diethylenetriamine with the appropriate phosphate ester in ethanol under acidic conditions. The polyphosphate structures were determined using FT-IR and 1H-NMR spectroscopies, and their elemental compositions were confirmed by EDX spectroscopy. Polyphosphates were added to poly(vinyl chloride) (PVC) at low concentrations to fabricate thin films. The PVC films were irradiated with ultraviolet light for long periods, and the effect of polyphosphates as the photostabilizer was investigated by determining changes in the infrared spectra (intensity of specific functional group peaks), reduction in molecular weight, weight loss, and surface morphology. Minimal changes we
... Show MoreA new light-weight nanocarbon prepared by spray-drying method to obtain particle size is 21.7 nm based of polylactic acid biodegradable film in antistatic packaging .Bio carbon (biochar) is obtained from plants and soils to naturally absorb and store carbon dioxide from the atmosphere . Therefor it has been used to support biodegradable polylactic acid (PLA) with to obtain 100% recyclable material.
Using plasticizer thymol of polylactic acid and biochar (bio carbon) as composites were prepared by a solution casting method with (0.5-10)wt% biochar. The composites characterized by FTIR, electrical conductivity, mechanical properties , contact angle and Colar and Brightness . Results show th
... Show MoreMS Elias, RGM AL-helfy, Plant Archives, 2019