To decrease the impact on the environment of building waste, the recycled aggregate may be used in various sustainable engineering applications, such as roller compacted concrete pavement (RCCP). This research examined how using recycled aggregate as a partial replacement for natural aggregate as coarse or fine affected the mechanical properties of roller-compacted concrete pavement. The recycled aggregate was crushed and sieved to coarse and fine aggregate before being used in the roller-compacted concrete pavement. Compressive strength, splitting tensile strength, and flexural strength were all evaluated after the samples were prepared at 28 and 90 days of curing. According to the study's findings, the partial replacement of coarse or fine aggregate with recycled aggregate by (10, 15 and 20%) by volume resulted in decreasing the mechanical properties and increasing the absorption and porosity of RCCP due to the contaminated cement paste on the surface of RCA when compared to the reference mix made with natural aggregate. Because the recycled aggregate contains un-hydrated cement particles, the results have improved after 90 days.
In this work the strain energy of tetrahedrane and its nitrogen substituted molecules were calculated by isodesmic reaction method according to DFT quantum chemical fashion, the used basis set was 6-31G/B3-LYP, in addition all structures were optimized by RM1 semi-empirical method. From the obtained data we estimate an empirical equation connect between strain energy of the molecule with charge functions represented by dipole moment of the molecule plus accumulated charge density involved within the tetrahedron frame plus the number of nitrogen atoms. The results indicate the charge spreading factors by polarization and processes are the most important factors in decreasing the strain energy.
Numerous integral and local electron density’s topological parameters of significant metal-metal and metal-ligand bonding interactions in a trinuclear tetrahydrido cluster [(Cp* Ir) (Cp Ru)2 (μ3-H) (μ-H)3]1 (Cp = η5 -C5Me5), (Cp* = η5 -C5Me4Et) were calculated and interpreted by using the quantum theory of atoms in molecules (QTAIM). The properties of bond critical points such as the delocalization indices δ (A, B), the electron density ρ(r), the local kinetic energy density G(r), the Laplacian of the electron density ∇2ρ(r), the local energy density
... Show MoreAn experiment in the semester, the second semester of the academic year (2022-2023), and the data used was not processed (the second test for two independent, inaccurate samples, the Bermon correlation coefficient, and the Spearman correlation coefficient), and the following results were reached: There is a statistically significant difference at the level of ( 0) average, 05) between the third grade who studied the plan for asking cluster questions, and between the average of those who studied the special feature according to the traditional method of selecting achievement, and enjoyed completing the specialization, choosing the experimental group, because the strategy of asking cluster questions is one of the externalities that... Lear
... Show MoreThe research aims to apply a modified SERVQUAL model to evaluate the quality of the educational services via conducting exploratory research for students from the College of Administration and Economics- Department of Business Administration- Evening studies at the University of Baghdad. Questionnaire of two parts was distributed to a sample of (72) students out of (720) students of the 2nd.,3rd. and 4th. year in the beginning of the second semester of the year 2008-2009 to measure the expectations and perceptions to the quality of the educational services. Five major dimensions were analyzed to see the gaps for (22) variables. The study concluded that there were (13) variables confirmed that the
... Show MoreThe experiment was conducted to study the effect of sodium chloride (NaCl) at the concentrations of 0.0, 0.5, 1.0 and 1.5% on the callus cells. The Iraq wheat variety was grown in vitro for the purpose of knowing the effect of salt stress on some indicators and cellular components of callus by using a randomized complete design, at the laboratories of tissue culture propagation date palm unit in the College of Agriculture / University of Kufa during the period 2014-2015. Fresh and dry weight, the rate of absolute growth, percentage of dry matter of callus, content of the callus cells of proline, total soluble carbohydrates, sodium and potassium ions, effectiveness of the enzymes catalase and peroxidase study shock salt proteins in callus we
... Show MoreAbstract
The aim of the current research is to prepare an integrated learning program based on mathematics standards for the next generation of the NYS and to investigate its impact on the development of the teaching performance of middle school mathematics teachers and the future thinking skills of their students. To achieve the objectives of the research, the researcher prepared a list of mathematics standards for the next generation, which were derived from a list of standards. He also prepared a list of the teaching competencies required for middle school mathematics teachers in light of the list of standards, as well as clarified the foundations of the training program and its objectives and the mathematical
... Show MoreNanoencapsulation, employing safe materials, holds substantial promise for enhancing bioactive compounds’ delivery, stability, and bioactivity. In this study, we present an innovative and safe methodology for augmenting the incorporation of the anticancer agent, curcumin, thereby inducing apoptosis by downregulating miR20a and miR21 expression. Our established methodology introduces three pivotal elements that, to our knowledge, have not undergone formal validation: (1) Novel formulation: We introduce a unique formula for curcumin incorporation. (2) Biocompatibility and biodegradability: our formulation exclusively consists of biocompatible and biodegradable constituents, ensuring t
Is the subject of the financial structure of the most important topics for which she received the interests of scientific research in the field of financial management , as it emerged several theories about choosing a financial structure appropriate for the facility and behavior change funding them , and in spite of that there is no agreement on a specific theory answer various questions in this regard , and a special issue of the financial structure optimization.
The objective of the research was to identify the most important theories of the structure of modern financial theory has been to focus on the capture of financial firms in two different stages of their life cycle , so-called growth and ma
... Show More