In this research the effect of grain size and effect of La2O3 doping on densification rate for the initial and intermediate stages of sintering were studied .The experimental results for α – cristobilite powder are modeled using ( L2-Regression ) technique in studying the effect of grain size and La2O3 doping using three particles size (6.12, 8.92, 13.6 ) µm, with undoped initial powder and with La2O3 doping . The mathematical simulation showes that the densification rates increase as the initial particles sizes decrease and vice versa. This shows that the densification depends directly on the initial compact density which reflects the contacts area between the particles . However the densification rates in the intermediate stages were enhanced compared with that of the initial stage .This is due to completion of neck growth that facilitates the mass transport between the grains ,and also, the presence of the massive grains due to the grain growth . Al so it is show that the doping enhances the densification rates in the intermediate stage due to that , the dopants act against the grain boundaries movement causing discourage closing of porosity and encourage escaping of voids enhances the densification rates .
Language is a vehicle for social values and ideologies that a man intends or attempts to express. Dramatic texts are one of the discursive practices that embody values and ideologies. What is expressed in dramatic text is deliberate because it is meant to affect other’s values, trends and ideologies in one way or another. Such ideologies and values are not explicit. To bring them out requires putting language under scrutiny to unveil what is implied. The present study attempts to analyze a dramatic script entitled Advice to Iraqi Women by the British playwright Martin Crimp in an attempt to unveil the intended political ideologies underlying the text. The title reflects a political aspect embedded in the word “Iraqi” that
... Show MoreObjective: The study aimed to identify the adolescents' family meal eating patterns, and find out the relationship between adolescents' family meal eating patterns and their weight control behaviors. Methodology: A descriptive study was conducted on impact of adolescents' family meal eating patterns upon their weight control behaviors in secondary schools at Baghdad city, starting from 20th of April 2013 to the end of October 2014. Non- probability (purposive) sample of 1254 adolescents were chosen from secondary schools of both sides of Al-Karkh and Al-Russafa sectors. Data was collected through a specially
This paper tackles methods of teaching conversation in Russian to students speaking Arabic. It analyses the differences between the two languages, as well as the difficulties and major errors faced by Arabic speakers studying Russian. Particularly, it looks at the difficulty of transforming spoken language. Finally, the paper suggests ways for teaching spoken language and treating the reasons behind making errors.
Аннотация
Данная статья рассматривает методы преподавания говорения на русском языке для носителей арабского яз
... Show MoreWe have designed, fabricated and studied the vertical axis wind turbine and its characterization. The system has been locally designed to pump water. It is considered as a one of the best options for low speed wind. The turbine has eight blades , each blade is 1.8m in length, and the area dimension of the turbine 3.6 m2 . were investigated the best characterization of the system at low wind speed are Power turbine depends on the wind speed. It was 280 Watt at 6m/s and 160 watt at 5m/s , and the power after the turbine decreasing to factor 1/3. The system torque was 20 N.m , Power coefficient cap 0.29 , Tip speed ratio 0.46. It is suitable to be used in Iraq region , and low cost for get the wat
... Show MoreThe current research dealt with the issue of organizational skillfulness as an entry point to reach strategic agility. The study has been tested in Iraq's mobile operators - Asia Cell, Zain Iraq and Cork Telecom. The study was applied to a sample of (93) managers distributed at various levels of management (board members, general managers, commissioners, department managers, people managers, unit managers, office managers). The survey used the questionnaire as a key tool for collecting data and information as well as personal interviews. It has sought to test a number of hypotheses related to correlation and influence relationships between the variables of the study, in order to answer the questions related to the problem of stud
... Show MoreOur recent work displays the successful preparation of Schiff_bases that carried out between hexane-2,5-dione and 2 moles of (Z)-3-hydrazineylideneindolin-2-one forming in Schiff-bases-(L), Which in turn allowed combining with each of the next metal ions: (M2+) = Ni, Mn, Zn, Cu and Co forming complexes_ in high stability. The formation of resulting Schiff_ bases (L) is detected spectrally using LC_Mss which gave approximately matching results with theoretical incomes, 1HNMR proves the founding of doublet signal of (2H) for 2NH, FTIR indicates the occurrence of two interfered imine bands and UV-VIS mean is also indecates the formation of ligand. On the other hand, complexes-based-Schiff were characterized using the s
... Show MoreIn this study an experimental work was done to study the possibility of using aluminum rubbish material as a coagulant to remove the colloidal particles from oily wastewater by dissolving this rubbish in sodium hydroxide solution. The experiments were carried out on simulated oily wastewater that was prepared at different oil concentrations and hardness levels (50, 250, 500, and 1000) ppm oil for (2000, 2500, 3000, and 3500) ppm CaCo3 respectively. The initial turbidity values were (203, 290, 770, and 1306) NTU, while the minimum values of turbidity that have been gained from the experiments in NTU units were (1.67, 1.95, 2.10, and 4.01) at best sodium aluminate dosages in milliliters (12, 20, 24, and 28) for
... Show MoreIn this work, solid random gain media were fabricated from laser dye solutions containing nanoparticles as scattering centers. Two different rhodamine dyes (123 and 6G) were used to host the highly-pure titanium dioxide nanoparticles to form the random gain media. The spectroscopic characteristics (mainly fluorescence) of these media were determined and studied. These random gain media showed laser emission in the visible region of electromagnetic spectrum. Fluorescence characteristics can be controlled to few nanometers by adjusting the characteristics of the host and nanoparticles as well as the preparation conditions of the samples. Emission of narrow linewidth (3nm) and high intensity in the visible region (533-537nm) was obtained.