In the present work, lead silicate glasses have been prepared with
different amount of lead oxide content. Structure properties such as
X-ray diffraction, AFM, and FTIR analyses have been done. The
exceeding of PbO content more than 25wt% revealed a decreasing in
density. The X- ray revealed that the strongest peak related to
Hexagonal silica dioxide and the other crystal phases formed were
related to silica oxide (SiO2) and lead oxide (PbO). Growth and
decayed phases in X-ray have been observed with changing lead
oxide content. Homogeneous surface was obtained using AFM
analyzer with an average diameter around 100 nm. Infrared spectrum
is characterized by the presence of large absorption band between
1200 and 900cm-1 and have its maximum at 1080 cm-1 which is
typical to stretching vibrations of Si–O–Si bonds, another bands
noticed were attributed to Pb–O–Pb, Pb–O–Si, [AlO4]-tetrahedron,
and to Si–O–Al bond.
Within connected speech, RP speakers tend to shorten stressed long vowels end diphthongs in pre. Forties consonants in the same syllable on the basis of complementary Distribution, i.e., the phonological environment decides the influence of the forties plosives and fricatives, as far as they are in find position preceded by stressed long vowels and diphthongs, or particular voiced consonants plus vowels. The Iraqi learners, then, face.
Let R be a commutative ring , the pseudo – von neuman regular graph of the ring R is define as a graph whose vertex set consists of all elements of R and any two distinct vertices a and b are adjacent if and only if , this graph denoted by P-VG(R) , in this work we got some new results a bout chromatic number of P-VG(R).
Improving the accuracy of load-deformation behavior, failure mode, and ultimate load capacity for reinforced concrete members subjected to in-plane loadings such as corbels, wall to foundation connections and panels need shear strength behavior to be included. Shear design in reinforced concrete structures depends on crack width, crack slippage and roughness of the surface of cracks.
This paper illustrates results of an experimental investigation conducted to investigate the direct shear strength of fiber normal strength concrete (NSC) and reactive powder concrete (RPC). The tests were performed along a pre-selected shear plane in concrete members named push-off specimens. The effectiveness of concrete compressiv
... Show MoreClimate change causes water shortage (water scarcity) in addition to the dams built by neighboring countries, which caused a lack of Iraq's water share. Therefore, evaluating the irrigation system requires considering its suitability, adequacy, and efficiency. Irrigation is considered adequate when it maintains water availability within the root zone, and if the amount to be added is determined, irrigation efficiency becomes possible by avoiding water loss. Babil Governorate is considered one of the agricultural governorates in the country that depends on its irrigation from Shatt Al-Hilla. The study area is the Elaj project. Three fields were selected for the project (B1, B2, and B3). These fields are lo
... Show MoreThis paper is devoted to the analysis of nonlinear singular boundary value problems for ordinary differential equations with a singularity of the different kind. We propose semi - analytic technique using two point osculatory interpolation to construct polynomial solution, and discussion behavior of the solution in the neighborhood of the singular points and its numerical approximation. Two examples are presented to demonstrate the applicability and efficiency of the methods. Finally, we discuss behavior of the solution in the neighborhood of the singularity point which appears to perform satisfactorily for singular problems.
In this paper, the static analysis for finding the best location of boxes inside the composite wing-box structure has been performed. A software ANSYS (ver.11) was used to analyses the Aluminum wing to find the maximum stresses reached in. These results are used as a base for the composite wingbox to find the numbers of layers and location of the box beam and its dimensions so that the composite wingbox may carry the same loading conditions in the Aluminum wing. Analysis showed that a composite wingbox having two boxes is better than the single or triple boxes wing based on stress to weight ratio. Mass saving of (40%) had been achieved when composite wing-box is used instead of Aluminum wing.
The world of Contemplations is a controversial concept among scholars, writers, thinkers and the public. The theory of the dialogue of souls indicates that souls communicate and think with each other despite the distances. Islamic studies have researched this concept, and this research paper aims to explain the concept of the world of Contemplations and what is the dialogue between God Almighty and the souls that God brought forth from the back of Adam and took from them the covenant and pledge to unify Him, and its effects on human life in this world. The researcher found that scholars and writers differ in proving the existence of the world of Contemplations despite the existence of examples of it in verses of the Holy Quran, and that the
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