In recent decades, tremendous success has been achieved in the advancement of chemical admixtures for Portland cement concrete. Most efforts have concentrated on improving the properties of concrete and studying the factors that influence on these properties. Since the compressive strength is considered a valuable property and is invariably a vital element of the structural design, especially high early strength development which can be provide more benefits in concrete production, such as reducing construction time and labor and saving the formwork and energy. As a matter of fact, it is influenced as a most properties of concrete by several factors including water-cement ratio, cement type and curing methods employed.
Because of accelerated curing is deemed one of methods that achieved high early age strength of concrete and has been grown only gradually. So, the prime aim of this research work is to provide information about the some desired properties of superplasticized and retarding concrete succumbed to accelerated curing methods, such as compressive strength and water absorption and compared it with their corresponding normally curing concrete. Besides, the research discusses the influence of surface texture of aggregate and over-dosing for admixture on performance concrete in such as that conditions. The test results revealed that effect of admixture on properties of concrete are dependent upon it dosage, surface texture for aggregate and
temperature used for curing
We propose a system to detect human faces in color images type BMP by using two methods RGB and YCbCr to determine which is the best one to be used, also determine the effect of applying Low pass filter, Contrast and Brightness on the image. In face detection we try to find the forehead from the binary image by scanning of the image that starts in the middle of the image then precedes by finding the continuous white pixel after continuous black pixel and the maximum width of the white pixel by scanning left and right vertically(sampled w) if the new width is half the previous one the scanning stops.
The inelastic C2 form factors and the charge density distribution (CDD) for 58,60,62Ni and 64,66,68Zn nuclei has been investigated by employing the Skyrme-Hartree-Fock method with (Sk35-Skzs*) parametrization. The inelastic C2 form factor is calculated by using the shape of Tassie and Bohr-Mottelson models with appropriate proton and neutron effective charges to account for the core-polarization effects contribution. The comparison of the predicted theoretical values was conducted with the available measured data for C2 and CDD form factors and showed very good agreement.
The aim of this work is to enhance the mechanical properties of the glass ionomer cement GIC (dental materials) by adding Zirconium Oxide ZrO2 in both micro and nano particles. GIC were mixed with (3, 5 and 7) wt% of both ZrO2 micro and nanoparticles separately. Compressive strength (CS), biaxial flexural strength (BFS), Vickers Microhardness (VH) and wear rate losses (WR) were investigated. The maximum compression strength was 122.31 MPa with 5 wt. % ZrO2 micro particle, while 3wt% nanoparticles give highest Microhardness and biaxial flexural strength of 88.8 VHN and 35.79 MPa respectively. The minimum wear rate losses were 3.776µg/m with 7 wt. % ZrO2 nanoparticle. GIC-contai
... Show MoreAbstract
The current research aims to identify the negotiation behavior of administrative teachers, as well as to identify the significance of the differences in negotiation behavior according to the variables (gender, scientific title, length of service). After confirming the psychometric characteristics of (20) items, the researchers applied the scale to (400) male and female administrative teaching staff who were randomly selected from the University of Baghdad for the academic year 2021/2022. The results showed the following the research sample has a negotiating behavior. There are no statistically significant differences between gender, scientific title, and length of service in the means of negotiating beha
... Show MoreA comparison study was made for the reaction of triruthenium carbonyl Ru3(CO)12 with azoarene ArN=NAr . This reaction was monitored in two kinds of solvents , toluene , and n- octane , which yielded new triruthenium carbonyl complex Ru3(μ3-NAr)2(CO)9 . The reactions of azoarenes ArN=NAr with Ru3(CO)12 formed the following trinuclear compound of Ru3((μ3- NAr)2(CO)9 (Ar-C6H4Br-4) in law yield . In addition , to new isomers species of mononuclear cyclometallated of Ru(BrC6H4N-NC6H4NBr-4)2(CO)2 in different percentages . The mechanism of the reaction domenstrates that the formation of trinuclear bis arylimido complexes , and ortho metallated was , the result of cleavage of nitrogen –nitrogen bond . Monitoring this gave evidence that the rea
... Show MoreMany new heterocyclic compounds including 4-thiazolidinones containing indole with triazole units were described. The new Schiff bases [VII] a, b and [VIII] a, b synthesized by condensation acid hydrazides [II],[VI] with different (aromatic) aldehydes in absolute ethanol. The refluxing equimolar amounts of the Schiff bases ([VII] a, b,[VIII] a, b) with thioglycolic acid in benzene led to get thiazolidin-4-ones derivatives ([IX] a, b and [X] ad). Finally, the new derivatives [XI] ac run out via the reacted compound [IX] a with different n-alkyl bromide (methyl bromide, ethyl bromide, and butyl bromide)
Many new heterocyclic compounds including 4-thiazolidinones containing indole with triazole units were described. The new Schiff bases [VII]a, b and [VIII]a,b synthesized by condensation acid hydrazides [II],[VI] with different (aromatic) aldehydes in absolute ethanol. The refluxing equimolar amounts of the Schiff bases ([VII]a,b, [VIII]a,b) with thioglycolic acid in benzene led to get thiazolidin-4-ones derivatives ([IX]a,b and [X]a-d). Finally, the new derivatives [XI]a-c run out via the reacted compound [IX]a with di
Four new binuclear Schiff base metal complexes [(MCl2)2L] {M = Fe 1, Co 2, Cu 3, Sn 4, L = N,N’-1,4-Phenylenebis (methanylylidene) bis (ethane-1,2-diamine)} have been synthesized using direct reaction between proligand (L) and the corresponding metal chloride (FeCl2, CoCl2, CuCl2 and SnCl2). The structures of the complexes have been conclusively determined by a set of spectroscopic techniques (FT-IR, 1H-NMR, and mass spectra). Finally, the biological properties of the complexes have been investigated with a comparative approach against different species of bacteria (E. coli G-, Pseudomonas G-, Bacillus G+,
... Show MoreAlthough the term' tautology' predicts negative connotation, it is often employed by poets and lyric writers to communicate more implied meanings. Through the use of tautological expressions, they exchange ideas, give more possibilities to readers to detect the meaning behind the tautological words and thus suggest details not openly communicated in the poem. Ten American song lyrics and ten American poems have been selected to be the data for the study. Data analysis is conducted on the basis of three steps:(i) identifying the type of tautology used ,(ii) detecting the syntactic realization of the tautology and (iii) finding the functions of the use of tautology in these lyrics and poems. The study concludes that song lyrics and p
... Show MoreThe aim of the current research is to identify the self-control of kindergarten teachers as well as to identify the significance of the differences according to a variable (years of service, academic achievement, specialization). Its final paragraphs consist of (35) paragraphs, and its psychometric properties were verified and the tool was applied to a sample of (400) teachers chosen randomly from kindergarten teachers affiliated to the General Directorates of Education in Baghdad, Rusafa, and Karkh for the academic year 2019-2020
In light of the objectives of the current research, the following results were reached
- The current research sample is from kindergarten teachers with self-contro
- There are diffe