The personality of the hero Salah al-Din al-Ayyubi (may God have mercy on him) came from the womb of jihad after difficult travails that the Arab Islamic nation experienced through the jihad of its loyal and honest sons who vowed themselves to God in defense of his religion and law, so between 490 AH - 540 AH outstanding jihadi leaders emerged who took upon themselves the responsibility of jihad and mobilizing the nation's energies To fight its enemies - the Franks, the Crusaders - in the Levant, and those leaders succeeded in achieving impressive victories over the Frankish military effort and regained some cities that were usurped by the Franks. Balak bin Bahram, Suqman, and Jakarmish, but these leaders could not maintain a state of unity, so the jihadist efforts of Imad al-Din Zangi came to draw a new state characterized by strength and organization, and succeeded in achieving strategic goals that changed the balance of power in favor of the Islamic military effort and prompted the Franks to assassinate him in the year 541 AH .
However, his son Nur al-Din Mahmud was up to the level of responsibility and a man of the stage that the nation desperately needed for his likes, because he completed the path of jihad drawn by his father, Imad al-Din Zangi. Training and leadership to later be his striking arm in the coming days, and their efforts culminated in uniting the word of the Muslims, ending the Fatimid state, and calling for the Abbasid caliph Al-Mustadi’ in the year 564 AH () Tikrit Castle was in honor of him and his trust in the year 525 AH, but the death of Muhammad and Masoud’s assumption of the sultanate came to end his emirate over Tikrit, as Masoud cut it off to Behrouz the charge of Baghdad and added to him all the adjacent states () and then moved to Mosul to work under the leadership of Imad al-Din Zangi, and it was the birth of Salah al-Din al-Ayyubi In the fortress of Tikrit on the day his father was removed from its emirate, so he moved with his family to Mosul under the care of Imad al-Din Zangi, and he grew up in that jihadi milieu until he emerged as a leading figure ().
Background: With the increasing demands for adult orthodontics, a growing need arises to bond attachments to porcelain surfaces. Optimal adhesion to porcelain surface should allow orthodontic treatment without bond failure but not jeopardize porcelain integrity after debonding.The present study was carried out to compare the shear bond strength of metal bracket bonded to porcelain surface prepared by two mechanical treatments and by using different etching systems (Hydrofluoric acid 9% and acidulated phosphate fluoride 1.23%). Materials and Methods: The samples were comprised of 60 models (28mm *15mm*28mm) of metal fused to porcelain (feldspathic porcelain). They were divided as the following: group I (control): the porcelain surface left u
... Show MoreThe effect of thickness variation on some physical properties of hematite α-Fe2O3 thin films was investigated. An Fe2O3 bulk in the form of pellet was prepared by cold pressing of Fe2O3 powder with subsequent sintering at 800 . Thin films with various thicknesses were obtained on glass substrates by pulsed laser deposition technique. The films properties were characterized by XRD, and FT-IR. The deposited iron oxide thin films showed a single hematite phase with polycrystalline rhombohedral crystal structure .The thickness of films were estimated by using spectrometer to be (185-232) nm. Using Debye Scherrerś formula, the average grain size for the samples was found to be (18-32) nm. Atomic force microscopy indicated that the films had
... Show MoreThe reaction oisolated and characterized by elemental analysis (C,H,N) , 1H-NMR, mass spectra and Fourier transform (Ft-IR). The reaction of the (L-AZD) with: [VO(II), Cr(III), Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II)], has been investigated and was isolated as tri nuclear cluster and characterized by: Ft-IR, U. v- Visible, electrical conductivity, magnetic susceptibilities at 25 Co, atomic absorption and molar ratio. Spectroscopic evidence showed that the binding of metal ions were through azide and carbonyl moieties resulting in a six- coordinating metal ions in [Cr (III), Mn (II), Co (II) and Ni (II)]. The Vo (II), Cu (II), Zn (II), Cd (II) and Hg (II) were coordinated through azide group only forming square pyramidal
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