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.
Perhaps masculinity and femininity in our Arabic language are among the linguistic issues that have occupied the attention of researchers, ancient and modern. Many books, works, and research have been written on this subject, but there is still something in it that must be revealed, clarified, and established, as the ancients did not classify the feminine and masculine into real, metaphorical, auditory, analogical,
Eat this research study features Technical Ceramics Islamic and Chinese The study of four chapters , such as the first chapter the general framework for research and containing the problem that put the following question: Mamdy effect features art on porcelain Islamic and Chinese ) , and whether there are dimensions of the aesthetic , intellectual and ideological in porcelain Islamic and Chinese with lies the importance of research in the promise of a qualitative study and add a scientific theme features art in porcelain Islamic and China , and the objectives of this study One was in the detection of features technical Ceramics Islamic and Chinese study examined the length of time the ninth century AD , and the tenth century AD , and in
... Show MoreThis article discusses the most beloved and creative dialect of the Arabs - the Iraqi dialect, despite its complexity, but it has a lot of beautiful foreign vocabulary. We followed a descriptive and historical approach, also tracked phonetic changes in this dialect, and then gave phonological explanations for these phenomena, trying to connect most of the phenomena with their historical roots in the standard Arabic "al-Fussha" and in ancient Arabic dialects. Most modern linguists have realized the need to study these dialects, since many of the modern dialect characteristics are only extensions of some ancient Arabic dialects, and do not refer them to the classical language. The study of modern Arabic dialects may be faced with a nu
... Show MoreAim of the research is the study of improving the performance of the thermal station south Baghdad and the main reasons for reduced its efficiency. South Baghdad power planet comprises (6) steam turbine units and (18) gas turbine units .The gas turbine units are composed of two groups: the first group is made up of gas units (1,2), each of capacity (123) MW. The design efficiency of gas turbine units is 32%. The actual efficiency data of steam units is 18.3% instead of 45% which is the design efficiency. The main reason for efficiency reduction of gas units is the rejected thermal energy with the exhaust gases to atmosphere, that are (450-510) ℃.The bad type of fuel used (heavy) fuel. Another reason for the low efficiency and has a neg
... Show MoreThis study deals with Aphid predators of the genus Coccinella L. recognized in different
regions of the world. They have been arranged systematically according to Korschefsky’s
catalogue (1931). The list includes sites of study and the reference (works) that consider
Coccinellids as predator. The study has revealed that there are thirteen Aphid predator species
belonging to the genus Coccinella L. in different places of the world, although there might be
other species that were not recorded by this work.
Abstract : The concept of moderation is one of the important concepts that have been discussed in political thought in general and in Islamic political thought in particular. It concerns the status of moderation and balance and the need of Islamic societies to apply them in contemporary times. The Islamic societies faced challenges facing Islamic advancement. And the right, which is the middle between the excessive and the excessive -and the exaggeration and cost-, and between negligence and default, moderation and integritybetween both two sides are: excessive and negligent". In addition, the concept of moderation and its intellectual roots have been sought in the Holy Quran and the noble prophetic, and the search for its charac
... Show MoreThis research deals with the formalities of the mortgage contract according to American law, We have given an overview of the provisions of this law related to the subject, We have also taken into consideration the role of American jurisprudence and the judiciary in finding legal solutions to the aforementioned formality, We have discussed the formality of mortgage in American law in two sections, In the first section we showed the formalism in immovable mortgage, and the second section specified to studying the formalism in movable mortgage.
Pollen morphology of 4 species (A. aucheri , A. auriculata, A. caucasica, A. nova) belonging to the genus Arabis L. in Iraq was examined by light microscope and scanning electron microscope to determine the significance of pollen features as a taxonomic characters. The results showed pollen grains of the species were monades, homopolar, tricolpate, and with medium size, but the species varied in shapes (polar and equatorial view), colpus length and width, exine thickness and exine ornamentation. Pollen colors were brown convert to brownish yellow.