A computational investigation is carried out in the field of charged –particle optics with the aid of numerical analysis method using the personal computer. The work is concerned with the design of electron gun with space-charge effect. The Finite element method (FEM) used in the solution of Poison's equation for determine the axial potential distribution of the two-electrode immersion lens operated under zero magnification condition , and from the solution of the paraxial ray equation the optical properties such as the focal length , spherical and chromatic aberration coefficients are determined, also a calculation of the brightness and perveance for the lens. The electrodes geometry was determined in two and three dimension with the aid of new drawing software called SIMION 7 and the electron beam trajectory under zero magnification conditions has been determine for these electrodes.
Iraq has a range of small and large marshes, which can be divided into two groups, a group of marshes feeding water from the Tigris and Euphrates rivers, and a group of marshes fed by the seasonal valleys coming from the desert plateau and the aljazera plateau.
The marshes have go through major changes, some of them turning into industrial lakes to store the flood waters of the Tigris and Euphrates rivers. Others have been dried up and turned into agricultural land. Others have dried up and the water has been returned to them in less quantities than before.
The purpose of this research is to but light on the changes that have occurred in these marshes, with the mention of marshes turned into industrial lakes or agricultur
... Show MoreThe language of theatre is made by a number of physical tools and moral elements. So as the actors, costumes, lightings and accessories represent the physical aspects of the show, they also represent its moral aspect too. When they transform from plastic words in the space of the visual show to become signs carrying its indications that give the meaning through the link, overlap and arrangement of its movements so as to finally look like as wording in a sentence carries the meaning and represent the language of theatre speech.
The show usually sends the recipient continuous signs that go beyond the limits of expressions that are conveyed by these tools, and that cover the largest part of the meaning. So what is kept hidden or unannoun
The population density witnessed by the capital, Baghdad, due to successive wars and unemployment, is linked to the phenomenon of urbanization, which is a global phenomenon that means the increasing tendency of the rural population to reside in cities (urban), especially concentration in the capital, Baghdad. Therefore, the phenomenon of urbanization is associated with 3 terms: migration, countryside, and city. Migration is when a person or a group leaves their place of residence to move to live in another place with the intention of staying in the new place for a long time. As for the countryside: they are the areas surrounding cities usually, and the countryside is characterized by natural and agricultural areas and is considered an outle
... Show MoreThe Iraqi houses flattening the roof by a concrete panel, and because of the panels on the top directly exposed to the solar radiation become unbearably hot and cold during the summer and winter. The traditional concrete panel components are cement, sand, and aggregate, which have a poor thermal property. The usage of materials with low thermal conductivity with no negative reflects on its mechanical properties gives good improvements to the thermal properties of the concrete panel. The practical part of this work was built on a multi-stage mixing plan. In the first stage the mixing ratio based on the ratios of the sand to cement. The second stage mixing ratios based on replacing the coarse aggregate quantities with the
... Show MoreIn the last few years, following the relative stability of the political, economic, and security environments, Iraq has embarked on a transformation towards an ambitious program of automation across various sectors. However, this automation program faces numerous challenges, including significant investments in technology and training, addressing social impacts, and combating widespread illiteracy
Research summary
Praise be to God, Lord of the worlds, and prayers and peace be upon the one who was the most eloquent of people in language and the most eloquent of them in eloquence, our Master Muhammad (peace and blessings of God be upon him).
To proceed... There is no doubt that many studies have preceded me in talking about chalk, each according to his own destination and view, and what I do not deny is that I benefited a lot from it, and it provided me with a lot of valuable information, and I liked to be one of those study pens, trying as much as possible To add something new and different in the study, far from similarity and repetition. Especially in the Abbasid study.
The babble in the Abbasid society was d
... Show MoreAbstract Political power in Lebanon is a fundamental objective of any political organization, whether political party or political group. Thus, there is a conflict of power. There are two kinds of political conflict that are differentiated by the idea of legitimacy. The competition is in the political system when the agreement between the social forces is considered legitimate, and the conflict is on the political system when the agreement between these forces ceases to be legitimate and Are working to topple it and seek to establish an alternative system. Therefore, the succession of power in Lebanon is a result of the competition and political conflict, which is in turn a result of the large number of regional and international players
... Show MorePraise be to God, who made the pegs of the earth and entrusted them with the task of keeping the earth from tilting, and prayers and peace be upon the one to whom the Qur’an was revealed, Muhammad, and upon his family and all his companions.
The topic of mountains is one of the important topics in human life, as God has associated great miracles with them that indicate the perfection of the power of God Almighty. God Almighty says: (And to the mountains, my palms have turned. This is worthy of every rational person to contemplate His signs, the Almighty, in this solid part and safety belt of the earth, in order to reveal the secrets of the mountains and uncover their treasures. The more the researcher studies the mountains and
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