Preferred Language
Articles
/
RRb4SIcBVTCNdQwCIUKs
Effect of internal curing on performance of self-compacting concrete by using sustainable materials
...Show More Authors

This paper is devoted to investigate the effect of internal curing technique on the properties of self-compacting concrete. In this study, self-compacting concrete is produced by using limestone powder as partial replacement by weight of cement with percentage of (5%), sand is partially replaced by volume with saturated fine lightweight aggregate which is thermostone aggregate as internal curing material in three percentages of (5%, 10%, 15%) for self-compacting concrete, and the use of two external curing conditions which are water and air. The experimental work was divided into three parts: in the first part, the workability tests of fresh self-compacting concrete were conducted. The second part included conducting compressive strength test and modulus of rupture test at ages of (7, 28 and 90) days. The third part included doing the shrinkage test at age of (7, 14, 21, 28) days. The results show that internally cured self-compacting concrete has the best workability and the best properties of hardened concrete which include (compressive strength, modulus of rupture) of externally cured self-compacting concrete with both water and air as compared with reference concretes. Also, the hardened properties of internally cured self-compacting concrete with percentage of (5%) with thermostone aggregate is the best as compared with that of percentages (10% and 15%) in both external curing conditions. In general, the results of shrinkage test have shown reduction in shrinkage of internally cured self-compacting concrete as compared with reference concretes and this reduction increases with increase in the thermostone aggregate content-within-self-compacting-concrete.

Crossref
View Publication
Publication Date
Mon Mar 27 2023
Journal Name
Iranian Journal Of Materials Science And Engineering
First-Principles Analysis of Cr-Doped SrTiO 3 Perovskite as Optoelectronic Materials
...Show More Authors

The influence of Cr3+ doping on the ground state properties of SrTiO 3 perovskite was evaluated using GGA-PBE approximation. Computational modeling results infered an agreement with the previously published literature. The modification of electronic structure and optical properties due to Cr3+ introducing into SrTiO 3 were investigated. Structural parameters assumed that Cr3+ doping alters the electronic structures of SrTiO 3 by shifting the conduction band through lower energies for the Sr and Ti sites. Besides, results showed that the band gap was reduced by approximately 50% when presenting one Cr3+ atom into the SrTiO 3 system and particularly positioned at Sr sites. Interestingly, substituting Ti site by Cr3+ led to eliminating the ban

... Show More
Preview PDF
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
Some machnical and thermal proprties of mullite prepared from iraqi starting materials
...Show More Authors

Some mechanical and thermal properties of mullite samples prepared by mixing different phases of alumina and silica powders have been studied according to ASTM methods the cold crushing strength of the sintcred bodies.With different porosity, at room temperature was in the range(18-54)Mpa

View Publication Preview PDF
Publication Date
Wed Jun 11 2003
Journal Name
Iraqi Journal Of Laser
Modeling of Plasma Affected Thermal Profile in Solids During Laser Materials Processing
...Show More Authors

A new scheme of plasma-mediated thermal coupling has been implemented which yields the temporal distributions of the thermal flux which reaches the metal surface, from which the spatial and temporal temperature profiles can be calculated. The model has shown that the temperature of evaporating surface is determined by the balance between the absorbed power and the rate of energy loss due to evaporation. When the laser power intensity range is 107 to108 W/cm2 the temperature of vapor could increase beyond the critical temperature of plasma ignition, i.e. plasma will be ignited above the metal surface. The plasma density has been analyzed at different values of vapor temperature and pressure using Boltzmann’s code for calculation of elec

... Show More
View Publication Preview PDF
Publication Date
Sat Jan 25 2020
Journal Name
Indian Journal Of Forensic Medicine & Toxicology
Color Stability of Different Aesthetic Resin Composite Materials: A Digital Image Analysis
...Show More Authors

View Publication
Crossref (1)
Crossref
Publication Date
Sun Jun 06 2010
Journal Name
Baghdad Science Journal
Preparation of Media for Growth and Isolation of Lactic Acid Bacteria by Using the Starch-Industry by- Products
...Show More Authors

By- products of corn starch industry were used to prepare media for propagation the lactic acid bacteria as a natural auxotroph. The by- products used were the corn steep water (S) and gluten extract (G) after a proper treatment to get them ready for media preparation. The results showed that it was possible to replace the peptone and meat extract by gluten extract in MRS medium. The growth was approximately similar to that obtained in standard MRS media. Corn steep water (S) was used as well and the growth enhanced by including Tween – 80 at 1% level. The later media named MZ, which was superior for growing standard and local strains and starters. The MZ medium modified by adding acetate and glacial acetic acid similarly to

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2023
Journal Name
The Egyptian Journal Of Hospital Medicine
Training of Skilled Force with The Different Medical Ball and Their Effect on Developing Some Special Physical Abilities and the Accuracy of Long Shooting Performance in Handball
...Show More Authors

View Publication Preview PDF
Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Modern Sport
Special exercises according to the Dynafoot data and its effect on the force index and the performance of the front straight air flip skill on the ground movements mat device
...Show More Authors

View Publication
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
The effect of temperature and density of different host spam in efficiency and performance life of the intruder
...Show More Authors

Studied competence spam to malicious moth figs at temperatures and Kagafat host different results showed that female intruder, despite their ability to shell larvae host and when densities of different, but it is able to lay eggs at a temperature of 14 + or -1 and finally urged the efficiency spam to malicious affected heavily host and that the greater the intensity of the host spam increased efficiency and its performance life

View Publication Preview PDF
Publication Date
Tue Dec 15 2020
Journal Name
Al-academy
The Formal Organization in Internal Spaces of Medical Laboratories: نور عامر علي-فاتن عباس لفته
...Show More Authors

تشغل الفضاءات الداخلية الطبية اهتمام واسع , لما توفره من رعاية صحية للمرضى ,فلابد ان يُهتَمْ بها من الجانب الوظيفي(الادائي), لتحقيق الراحة البصرية والنفسية والجسدية لغرض الوصول الى الاداء الجيد للكادر الطبي, ولهذا وجد ضرورة التعرف على تلك الفضاءات الداخلية بشكل اعمق , وهل انها ملاءمة للمرتكزات التصميمية المتعارف عليها؟ , لذلك تم تسليط الضوء على الفضاءات الداخلية للمختبرات الطبية, وقد تناول البحث المشكلة واه

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Dec 31 2011
Journal Name
Al-khwarizmi Engineering Journal
Simulation of Oxygen Mass Transfer in an Internal Loop Airlift Reactor with Axial Dispersion Model
...Show More Authors

The effect of superficial gas velocity within the range 0.01-0.164 m/s on gas holdup (overall, riser and down comer), volumetric oxygen mass transfer coefficient, liquid circulation velocity was studied in an internal loop concentric tubes airlift reactor (working volume 45 liters). It was shown that as the usg increases the gas holdup and also the liquid circulation velocity increase. Also it was found that increasing superficial gas velocity lead to increase the interfacial area that increases the overall oxygen mass transfer coefficient. The hydrodynamic experimental results were modeled with the available equations in the literature. The predicted data gave an acceptable accuracy with the empirical data.

The final

... Show More
View Publication Preview PDF