Epoxy resin has many chemical features and mechanical properties, but it has a small elongation at break, low impact strength and crack propagation resistance, i.e. it exhibits a brittle behavior. In the current study, the influence of adding kaolin with variable particle size on the mechanical properties (flexural modulus E, toughness Gc, fracture toughness Kc, hardness HB, and Wear rate WR) of epoxy resin was evaluated. Composites of epoxy with varying concentrations (0, 10, 20, 30, 40 weights %) of kaolin were prepared by hand-out method. The composites showed improved (E, Gc, Kc, HB, and WR) properties with the addition of filler. Also, similar results were observed with the decrease in particle size. In addition, in this study, mult
... Show MoreThe photoconductivity and its dependence on light intensity have been investigated in a-Ge20Se80 thin films as a function of temperature between (293–323)K. The result showed that the photoconductivity and photosensitivity increase with increase of annealing temperature. This behavior is interpreted in terms of the dispersive diffusion –controlled recombination of localized electrons and holes.
Abstract We have been studied and analysis the electronic current at the interfaces of Au/PTCDA system according to simple quantum mode for the electronics transition rate due to postulate quantum theory. Calculation of electronic current were performed at interface of Au/PTCDA as well as for investigation the feature of electronic density at this devices. The transition of electronic current study under assume the electronic state of Au and PTCDA were continuum and the states of electrons must be closed to energy level for Au at Fermi state, and the potential at interface feature depended on structure of Au and PTCDA material. The electronic transition current feature was dependent on the driving force energy that results of absorption ene
... Show MoreThe rapid success and the field dilation of Daish organization in both Iraq and Syria make academic institutes and research centers to pay attention to its propaganda means to gain its public opinion, and to further investigation about new methods employed by this organization to disseminate its messages to the public, particularly young people in large areas of the world. This organization uses traditional propaganda techniques on psychological war and its levels, social network sites and platforms that are distributed online. This study seeks to expose more persuasive methods used by the organization to gain multiple classes of society and to disseminate its extremist ideological thoughts. It also studies the psychological operation an
... Show MoreThis research aims to measure the impact of applying bank governance mechanisms in reducing the financial risks of banks listed on the Palestine Stock Exchange, and to answer research questions and test hypotheses for the study, researchers adopted the descriptive and analytical approach, and data were collected from the annual financial reports of the banks listed on the Palestine Exchange during the period between (2009-2018), as a time series for the purpose of finding, analyzing and measuring the effect between the study variables during this period by (60) views for each of the study variables, using the statistical analysis program views(9) to enter, process and analyze the data. The results of the study proved that there i
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