This paper provides the result of an investigation to use of crushed clay brick as
aggregates in producing concrete. Eight different crushed clay brick aggregate concretes were
used in this investigation. Compressive strength, splitting tensile strength and pulse velocity of
crushed clay brick aggregates concrete were determined and compare to natural aggregate
concrete. The compressive strength of crushed clay brick aggregates concretes were always
lower than the compressive strength of natural aggregates concrete regardless the age of
concrete, but the crushed clay brick aggregates concrete showed better performance as the age of
concrete increases and average reduction in compressive strength were 33.5% at the age of 7
days but it becomes only 20% at the age of 56 days compared to natural aggregates concrete. The
splitting tensile strength of crushed clay brick aggregates concrete were always lower than
natural aggregate concrete, the reduction in splitting tensile strength of crushed clay brick
aggregates concrete is ranging between 11 and 26% with an average reduction of about 18.5%
compared to natural aggregates concrete. The pulse velocity of crushed clay brick aggregates
concrete were also lower than natural aggregates concrete, the reduction in pulse velocity of
crashed clay brick aggregates concrete is ranging between 6 and 22% with an average reduction
of about 14% compared to natural aggregates concrete.
Background: Computerized tomography scan can show the detailed anatomy of the nose and paranasal sinuses. The sphenoid sinus is a very important corridor for the skull base because of its central position. This sinus has a great range of variation and can put structures around at risk during surgery. This study aims to examine the variation of the sphenoid sinus, and its relation to other structures around it, in this sample of Iraqi patients. Materials and Methods: CT scans of 122 patients, were obtained, and submitted for examination and measurements, during the period between September 2020 and September 2021. Observation of The sphenoid sinus pneumatization pattern, clival extension, Onodi cell, and lateral pneumatization of SS.
... Show MoreEducation is a process of learning and education at the same time. As the conditions of modern life necessitate every person to keep learning, education has become a necessity to meet life needs. The society today is concerned with the educational process and aims to live up the expectations. Since education is an integral part of education and its means, it has become as a mean to achieve its purposes. The educational environment was a traditional environment limited to specific inputs, possibilities and stimulus of both teacher and student. Due to the latest advancement, the educational environment has been expanded to become a rich, with strong connections. It has expanded to encompass the entire global environment. The current
... Show MoreThe purpose of the current research is to identify the most important problems that primary school students suffer from inside and outside the classroom from the point of view of their teachers. A sample of (100) male and female teachers was chosen from the Rusafa\ second Directorate for the academic year (2018-2019). The research tool was prepared after reviewing literature related to the issue of problems and difficulties facing students or students in the school stage and even at university. The researcher reached several results that were discussed in the fourth chapter, with a set of conclusions based on the results of the research, and come up with several recommendations and suggestions.
The rheological behavior among factors that are present in Stokes law can be used to control the stability of the colloidal dispersion system. The felodipine lipid polymer hybrid nanocarriers (LPHNs) is an interesting colloidal dispersion system that is used for rheological characteristic analysis. The LPHNs compose of polymeric components and lipids. This research aims to prepare oral felodipine LPHNs to investigate the effect of independent variables on the rheological behavior of the nanosystem. The microwave-based technique was used to prepare felodipine LPHNs (H1-H9) successfully. All the formulations enter the characterization process for particle size and PDI to ascertain the colloidal properties of the prepared nanosystem t
... Show Moreناقش البحث في طياته عدداً من القضايا الرئيسة المتعلقة بالتقييم الاستراتيجي والإطار العام للخطة الاستراتيجية المقترحة لشركة نفط ميسان للسنوات الخمس المقبلة (2020_2024)، وهدف هذا البحث يتمحور في تقييم عملية صياغة استراتيجية شركة نفط ميسان لتحديد نقاط القوة وتعضيدها ومواطن الضعف ومحاولة معالجتها لتجنب الوقوع بها عند وضع استراتيجية للسنوات القادمة، وعلى هذا الاساس فان مشكلة البحث تكمن في مدى نجاح الاستراتي
... Show MoreA series of heterogeneous basic catalysts of CaO, MgO and CaMgO2 at different calcination temperature were synthesized via solution combustion method. Different characterization techniques have been carried out to investigate the structure of the produced catalysts i.e. X-ray diffraction (XRD), particle size analyzer, morphology by atomic force microscope (AFM) and reflection using UV-VIS diffuse reflectance spectra. The particles size analyzer revealed that the mixed oxide catalysts calcined at different calcination temperature possess smaller nano size particles compared to pure CaO. Moreover, the energy band gap was calculated based on the results of diffuse reflectance spectra. The energy band gap was redu
... Show Moreبناء على ما تقدم يتضح ان القطاع العام والقطاع الخاص ليسا موقفا ايدولوجيا انتقائيا، وانما هو انبثاق من العمود الفقري للصيرورة الرأسمالية القائمة على تقديس الملكية الخاصة، وان الادوار التي يمكن ان يلعباها ليسا منعزلين عن الحركة العامة للاقتصاد في كليته، وليس هما ابنا السياسات الاقتصادية، والبناء الفوقي بقدر ماهما نتاج الحركة الموضوعية وصيرورة التطور الاجتماعي معبرا عنها في تطور علاقات الانتاج وقوى الانتا
... Show MoreThe experimental study showed the use of closed cavity wall (the thickness of the cavity 5cm) made a percentage reduction in the cooling load caused by heat gain from the wall by (21.5 %) compared with the conventional wall. also the thermal resistance of the closed cavity was an average (0.2 m2.oC/W).
The experimental results of the study showed that the use of closed cavity wall reduced the average temperature of the inner surface of the wall during the day, and that the reduction was an average (0.45 oC) when compared with the conventional wall , as well as the use of closed cavity wall reduced the temperature difference range of the inner surface of the wall during the day, and that the
... Show MoreThe dispersion relation of linear quantum ion acoustic waves is derivate according to a fluid approach that depends on the kinetic description of the systems of charged particles model. We discussed the dispersion relation by changing its parameters and graphically represented. We found through graphs that there is full agreement with previous studies on the subject of interest. That motivates us to discuss the dispersion relation of waves depending on the original basic parameters that implicitly involved in the relationship which change the relationship by one way or another, such as electron Fermi temperature and the density at equilibrium state.
In this paper, a harvested prey-predator model involving infectious disease in prey is considered. The existence, uniqueness and boundedness of the solution are discussed. The stability analysis of all possible equilibrium points are carried out. The persistence conditions of the system are established. The behavior of the system is simulated and bifurcation diagrams are obtained for different parameters. The results show that the existence of disease and harvesting can give rise to multiple attractors, including chaos, with variations in critical parameters.