Concrete is the main construction material of many structures. Exposing to loads creates cracks in concrete, which reduce the performance and durability. The decrease of concrete cracks becomes a necessity demand to ensure more durability and structural integrity of the concrete structure. Autogenous healing concrete is a kind of new smart concretes, which has the ability to reclose its cracks by means of itself. Concrete self-healing is a type of free repairs processes, which is reduce direct and indirect cost of maintenance and repairing. This work targets to inspect the mechanical properties of concrete after using two combinations of two materials (20 kg/m3 calcium hydroxide Ca(OH)2 and 2 kg/m3 sodium carbonate Na2CO3 and 30 kg/m3 calcium hydroxide and 3 kg/m3 sodium carbonate) as a partial replacement of cement to work as self-healing agents. The paper reports and study the compressive, flexural and splitting tensile strengths and ultrasonic pulse velocity tests’ results at 7, 28 and 90 days of concrete age. Use of two combinations of calcium hydroxide and sodium carbonate, as healing agents, enhanced the mechanical properties of concrete and reduced the width of concrete cracks with time. The concrete compressive strength was increased after curing for 90 days by 9.3 and 11.1 %, respectively. The flexural strength was improved by 14.3 and 15.9 %, respectively. Also, the splitting tensile strength was enhanced by 6.9 and 9.3 %, respectively.
The present study aims to illuminate the assessment of the Turkish elite of the role of the Turkish media in forming the attitudes of public opinion vis a vis the attempted military coup of 15 July 2016. The authors utilized the survey method of a nominal sample of 315 individuals, equally distributed among the three foremost categories of the Turkish elite, namely: the political academic, and media elite. The foremost findings of the study are that the orientation of the coverage of the Turkish media of the events of the attempt military coup of 15 July, based on the perception and assessment of the Turkish elite, was positive to a high degree; it refuted the news and the inciting information given to foreign media revealed the bloodine
... Show MoreGenetic polymorphisms of genes whose products are responsible for activities, such as xenobiotic metabolism, mutagen detoxification and DNA-repair, have been predicted to be associated with the risk of developing lung cancer (LC). The association of LC with tobacco smoking has been extensively investigated, but no studies have focused on the Arab ethnic- ity. Previously, we examined the association between genetic polymorphisms among Phase I and Phase II metabolism genes and the risk of LC. Here, we extend the data by examining the correlation of OGG1 Ser326Cys combined with CYP1A1 (Ile462Val and MspI) and GSTP1 (Ile105Val and Ala103Val) polymorphisms with the risk of LC. Polymerase chain reaction- restriction fragment length polymorphism (
... Show Morethis research concern with material function subject by using it in Baghdad education in formational places , because it considered as one of the most important spaces which needs a material presentation for the interior consistings that shares with prepairing the right mode for thos who use these spaces, regarding to that this research includes four chapters: Chapter one: concern with the research problem represented by the following question: can we use the material to place the hole spaces of information place ? So the aim of the research seems very obvious in functioning the material these places, and to take a close view on the importance of the research the theory , implementation and objective limits also concerning the terminolog
... Show MoreThis study tests the effect of a large number of independent variables that control the growth of the total productivity, which amounted to 112 variables, gathered from what is mentioned in the specialized theoretical and applied literature. The data for these variables were taken from global reports of sound international organizations and reliable databases covering the period 1991-2016. The data of the dependent variable, the growth of the total factor productivity, were taken from the database of the world development indicators. The study covered 61 countries for which data were available. The study included three regression models to explain
... Show MoreThe mechanism for selecting the President of the Republic and his constitutional powers under the Constitution of the Republic of Iraq
The aim of the research is to demonstrate the importance of leadership empowerment in its dimensions (knowledge, participation in decision-making, incentives, trust between the leader and subordinate, delegation of authority and communication) and its impact on enhancing the effectiveness of the company in its dimensions Represented by (achievement of objectives, quality of insurance service, adaptation to work environment and job satisfaction), by adopting the questionnaire as a main tool in collecting data from officials in the National Insurance Company, numbering (56) surveyed in job sites (section manager, division official and unit official) Their answers were analyzed using the SPSS statistical program in calculating the a
... Show MoreAbstract:
Central banks seek to control and supervise credit and follow it up effectively due to the high credit risks surrounding it that may lead to damage to banks, and may even lead to damage to the reputation and confidence of the banking system as a whole.
The main role of supervisory control is to control credit by controlling it from excessive expansion during periods of economic inflation or its revitalization and improvement and expansion of credit transactions in cases of economic recession, or when central banks desire to support the national economy or support a sector of various
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