Gamma - irradiation effect on polymethylmethacrylate (PMMA) samples has been studied using Positron Annihilation Lifetime (PAL) method. The orthopositronium (o-Ps) lifetime τ3, hence the o-ps parameters, the volume hole size (Vh) and the free volume fraction (Ꞙh) in the irradiated samples were measured as a function of gamma-irradiation dose up to 28.05 kGy. It has been shown that τ 3, Vh, and Ꞙh, are increasing in general with increasing gamma-dose, to reach a maximum percentage increment of 22.42% in τ3, 60% in Vh and 29.5% in Ꞙh, at. 2.55 kGy, whereas τ2 reaches maximum increment of 119. 7% at 7.65 kGy. The results suggest that gamma-irradiation induces structure changes in PMAM, causing degradation in the main chains, and the presence of oxygen Causes reduction in the amorphous regions ; oxygen and the peroxy radicals form cross-linking at reactive sites between neighboring chains, giving a net reduction of the degradation yield.
After looking at the books of the first two grammarians, may God have mercy on them and reward them for what they have provided us with the rules of service to the Book of God and service to Arabic, we must highlight some of the things that the grammarians wanted to clarify, which did not come out of what they proved, but we are working on the statement of the issuance of the passport Provisions from the syntactic industry, and whether it is intended to prove a rule is not very added to the statement of speech, and we know that language, any language was the function of understanding; therefore they said: (speech is a useful word that indicates the benefit improves silence on them), and this concept between Grammatical controls and conte
... Show MorePure and doped barium titanate with Mg2+ ion at two molar ratios x= (5%, 10%) mol. has been synthesized by solid state reaction technique. The powders sintered at two temperatures (1000 °C and 1400 °C). An XRD technique was used in order to study the crystal structure of pure and doped barium titanate, which confirmed the formation of the tetragonal phase of BaTiO3, and then calculate the lattice parameters of pure and doped barium titanate, the addition of magnesium ion Mg2+ can lead to decreases lattice parameters.
This study aims to reveal the semiotic of “March of Return” cartoon in the Palestinian journalism, topics, Symbols and semantics that were covered.
This study is descriptive. It uses the survey method. Content analysis, and methodological comparison was also used.
The researcher chose an intentional sample of Palestine and Al-Hayat Al-Jadida newspapers for one year from March 30, 2018 to March 31, 2019, through a comprehensive inventory of all cartoons of the return marches during this period, which amounted to 59 cartoons.
The study has reached the following findings:
Newspapers cartoons focused on the topics of durability of the protester
... Show MoreDespite the global economic downturn, online e-commerce, especially the sale of counterfeit goods, continues to witness a rise in sales, and one of the important players in e-commerce is the owners of e-commerce auction sites. Although they do not have a direct role in trademark infringement, they still consider them indirectly responsible (secondary liability) for infringing on their trademarks. Thus, many cases have been filed by the owners of the original trademarks (which have been infringed by persons who have sold some of the goods and products that are imitating their marks through some electronic auctions) against the owners of those auctions. In view of the international character of the Internet, in different countries, and despit
... Show MoreLandlocked countries are displayed geopolitical new geo-political and intended to
countries that do not have sea views, a phenomenon present in four continents of the world
are: Africa, Europe, and Asia, and South America and the number arrived at the present time
to the (44) state the largest number of them in the continent it arrived in Africa (16) countries
in Asia (13) countries and Europe (13) In the State of South America two. This phenomenon
emerged due to the division of federations and empires and colonial treaties and others. But
the negative effects suffered by these countries may vary from one country to another, since
these countries in the continent of Europe, for example, is different from the same cou
The aim the research that definition on the impact a lot of Analysis and evaluation jobs impact in support the employees performance the property that are Analysis and evaluation jobs is one of the jobs however of the human resource management on organization and the impact footpace big on the chractericties and performance of the people and the impact that success of the organization , And here problem stool of the research in the omission the role for the Analysis and evaluation jobs impact in support the employees performance from the upward management in the organization , Polls were adopted as tools for obtaining data and the Depart
... Show MoreABSTRACT This study closely investigates the elements of Sigmund Freud’s theory “The Uncanny” in one of Larson’s most famous novels. Although the novel touches upon racial issues, the study explores the mysterious relationship between Irene and Clare based on the main features of Freud’s “The Uncanny,” which are represented by hidden sexual desire, envy, supernatural power, and double characters. The aspect of the sexual desire is indicated in the novel by sexual undertones expressed by Irene towards Clare’s physical features. Envy in the novel is expressed by Irene who shows resentful longing aroused by Clare’s possessions and qualities due to her passing to the white community. The aspect of omnipotence of thoughts is in
... Show MoreAbstract
In the present work, thermal diffusivity and heat capacity measurements have been investigated in temperature range between RT and 1473 K for different duplex stainless steel supplied by Outokumpu Stainless AB, Sweden. The purpose of this study is to get a reliable thermophysical data of these alloys and to study the effect of microstructure on the thermal diffusivity and heat capacity value. Results show the ferrite content in the duplex stainless steel increased with temperature at equilibrium state. On the other hand, ferrite content increased with increasing Cr/Ni ratio and there is no significant effect of ferrite content on the thermal diffusivity value at room temperature. Furthermore, the heat capacity of all sam
... Show MoreA modified chemical method was used to prepare titanium dioxide nanoparticles (TiO2 NPs), which were diagnosed by several techniques: X-ray diffraction, Fourier transform infrared, field emission scaning electron microscopy, energy disperse X-ray, and UV-visible spectroscopy, which proved the success of the preparation process at the nanoscale level. Where the titanium oxide particles have an average particle size equal to 6.8 nm, titanium dioxide particles were used in the process of adsorption of Congo red dye from its aqueous solutions using a batch system. The titanium oxide particles gave an adsorption efficiency of Congo red dye up to more than 79 %. The experimental data of the adsorption process were analyzed with kinetic models and
... Show More