Effect of nano and micro SiO2 particles with different weight percent (2,4,6,8 and 10) %wt on the Interlaminar fracture toughness (GIc) of 16-plies of woven roving glass fiber /epoxy composites prepared by hand lay – up technique were investigated. The specimens were tested using DCB test (mode I).
Area method was used to compute the interlaminar fracture toughness. The results show that, GIc would increase with the increasing in the filler content, the main failure in microcomposites and nanocomposites was delamination in the layers, the delamination reduced with increasing in the filler content.
The study aimed to effect of speed and die holes diameter in the machine on feed pellets quality. In this study was measured pellet direct measurement (%), pellet lengths (%), pellet durability (%) and pellet water absorption (%). Three die speeds 280, 300, and 320 rpm, three diameters of die holes in the machine 3, 4, and 5 mm, have been used. The results showed that increasing the pellet die speeds from 280 to 300 then to 320 rpm led to a significant decrease in direct measurement, pellet durability, and pellet water absorption was increased, whereas it did not significantly affect the pellet lengths. Increasing the die holes diameter from 3 to 4 then to 5 mm led to a significant de
Gold, silver and nickel used as electrodes in the fabrication of perovskite solar cell by using thermal evaporation deposition method with direct structure FTO\ TiO2\ MAPbI3\ spiro-MeOTAD\ metal electrode. The cell efficiency was compared between the electrodes material as a function of time to explaining the effect of these metals electrode on cell performance, X-ray diffraction pattern showed that the samples that contain gold and nickel do not contain a compound indicating the interaction of the metal with the components of the cell or the formation of a new compound, while in the cell containing silver it was found that silver iodide is fo
The aim of this research is to study the optical properties of carbon-magnesium plasma resulting from arc discharge with explosive wire technique, where the energy gap of each of carbon and magnesium and the carbon-magnesium bond for three values of the wire exploding current (50,75,100 amperes) was studied. It was found that the energy gap for each of carbon and magnesium decreases with increasing the current, the X-ray diffraction of magnesium and the carbon-magnesium suspension was studied, and FTIR of the carbon-magnesium suspended carbon was studied for three values of the exploding current (50, 75, 100 amperes) and the type of bonds for carbon and magnesium was determined. To ob
: Porous silicon (n-PS) films can be prepared by photoelectochemical etching (PECE) Silicon chips n - types with 15 (mA /cm2), in15 minutes etching time on the fabrication nano-sized pore arrangement. By using X-ray diffraction measurement and atomic power microscopy characteristics (AFM), PS was investigated. It was also evaluated the crystallites size from (XRD) for the PS nanoscale. The atomic force microscopy confirmed the nano-metric size chemical fictionalization through the electrochemical etching that was shown on the PS surface chemical composition. The atomic power microscopy checks showed the roughness of the silicon surface. It is also notified (TiO2) preparation nano-particles that were prepared by pulse laser eradication in e
... Show MoreNanofluids are proven to be efficient agents for wettability alteration in subsurface applications including enhanced oil recovery (EOR). Nanofluids can also be used for CO2-storage applications where the CO2-wet rocks can be rendered strongly water-wet, however no attention has been given to this aspect in the past. Thus in this work we presents contact angle (θ) measurements for CO2/brine/calcite system as function of pressure (0.1 MPa, 5 MPa, 10 MPa, 15 MPa, and 20 MPa), temperature (23 °C, 50 °C and 70 °C), and salinity (0, 5, 10, 15, and 20% NaCl) before and after nano-treatment to address the wettability alteration efficiency. Moreover, the effect of treatment pressure and temperature, treatment fluid concentration (SiO2 wt%) and
... Show MoreThe Hubble telescope is characterized by the accuracy of the image formed in it, as a result of the fact that the surrounding environment is free of optical pollutants. Such as atmospheric gases and dust, in addition to light pollution emanating from industrial and natural light sources on the earth's surface. The Hubble telescope has a relatively large objective lens that provides appropriate light to enter the telescope to get a good image. Because of the nature of astronomical observation, which requires sufficient light intensity emanating from celestial objects (galaxies, stars, planets, etc.). The Hubble telescope is classified as type of the Cassegrain reflecting telescopes, which gives it the advantage of eliminating chromat
... Show MoreThis present study is aimed at deciding the impact of exercises adapted to the ranges of movements of the arm on the performance of javelin throwing. As long as javelin throwing is quite a complex athletic event that presupposes a considerable amount of strength, speed, and biomechanical accuracy, it is crucial to learn whether the exercises designed to target the peculiarities of arm movements can have a positive effect on the performance of javelin throwers. To the study, experimental research with a single group of six youth javelin throwers was carried out. Before and after the eight-week training program, the pre-tests and post-tests were conducted to find the results of training with a specific focus on resistance exercises. Significa
... Show MoreThe first flow injection spectrophotometric method is characterized by its speed and sensitivity which have been developed for the determination of promethazine-HCl in pure and pharmaceutical preparation. It is based on the in situ detection of colored cationic radicals formed via oxidation of the drug with sodium persulphate to pinkish-red species and the same species was determined by using homemade Ayah 3SX3-3D solar flow injection photometer. Optimum conditions were obtained by using the high intensive green light emitted diode as a source. Linear dynamic range for the absorbance versus promethazine-HCl concentration was 0-7 mmol.L-1, with the correlation coefficient (r) was 0.9904 while the percentage linearity (r2%) was 98.09%. the L.
... Show More