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Fire Flame Influence on the Behavior of reinforced Concrete Beams Affected by Repeated Load
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The influence and hazard of fire flame are one of the most important parameters that affecting the durability and strength of structural members. This research studied the influence of fire flame on the behavior of reinforced concrete beams affected by repeated load. Nine self- compacted reinforced concrete beams were castellated, all have the same geometric layout (0.15x0.15x1.00) m, reinforcement details and compressive strength (50 Mpa).

To estimate the effect of fire flame disaster, four temperatures were adopted (200, 300, 400 and 500) oC and two method of cooling were used (graduated and sudden). In the first cooling method, graduated, the tested beams were leaved to cool in air while in the second method, sudden, water splash was used to reduce the temperature. Eight of the tested beams were divided in to four groups, each were burned to one of the adopted temperature for about half an hour and cooled by the adopted cooling methods (one by sudden cooling and the other by graduated cooling). After burning and cooling the beams were tested under the effect of repeated load (loading – unloading) for five cycle and then up to failure.

As a compared with the non- burned beam, the results indicated that the ultimate load capacity of the tested beams were reduced by (16, 23, 54 and 71)% after being burned to (200, 300, 400 and 500) oC , respectively, for a case of sudden cooling and by (8, 14, 36 and 64)% , respectively, for a case of graduated cooling. It was also found that the effect of sudden cooling was greater than that in a case of graduated cooling.

Regarding the failure mode, there was a different between the non-burred beam and the other ones even that all of them had the same geometric layout, compressive strength and reinforcement details. The failure mode for all burned beams was combined shear- flexure failure which was belong to the reduction in the compressive strength of the concrete due to the effect of the temperature rising , while the failure mode of the non-burned beam was flexure failure which was compatible with the preliminary design. It was also detected that the residual deflection proportion directly with the temperature, as the temperature increase to (200, 300, 400 and 500) oC the residual deflection compared with the non-burned beam increased by (32, 48, 326 and 358)% for a case of sudden cooling and by (13, 29, 303 and 332)%  for a case of graduated cooling. Another effect was appear represented by the method of cooling, the results showed that the sudden cooling had more effect on the residual deflection than the graduated cooling by (15-6)% approximately. To vanish the residual deflection, numbers of cycle (loading-unloading) were required. It was found that this number increase as the temperature of burning increased and it’s also larger in a case of sudden cooling.

 

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Publication Date
Fri Sep 01 2006
Journal Name
Journal Of Thermoplastic Composite Materials
The Thermoelectrical Behavior of PEO Films Doped with MnCl<sub>2</sub> Salt
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The poly(ethylene oxide) polymer (PEO) is doped with fine powder of MnCl2 salt and thin films of thickness (50–150 mm) with salt content (0, 5, 10, 15, and 20 wt%) are obtained. The AC electrical conductivity and dielectric constants are studied as a function of temperature through an impedance technique. It is found that AC conductivity increases and the calculated activation energy decreases with increasing temperature due to enhancement of the ionic conduction in the film bulk. The dielectric constants of the doped membranes increase with temperature. It is found that the peak value of the tanloss is shifted to a higher frequency at higher temperatures. The dielectric behavior is explained on the basis of

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Publication Date
Wed Apr 03 2024
Journal Name
International Journal Of Ebusiness And Egovernment Studies
THE IMPACT OF STRATEGIC CONSENSUS ON ORGANIZATIONAL PERFORMANCE BY MEDIATING STRATEGIC ALIGNMENT
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This study investigates the influence of Strategic Consensus (SC) on Organizational Performance (OP), with Strategic Alignment (SA) serving as a mediating variable, within private academic institutions in Iraq. The research utilized scales developed to measure each variable: SC, OP, and SA, all of which are unidimensional. The sample comprised 131 senior participants, including deans and faculty council members, with questionnaires distributed across three institutions: Dijla University College (35 respondents), Baghdad College of Economic Sciences (31 respondents), and the University of Uruk (65 respondents). Data analysis employed various statistical techniques, including normality testing, confirmatory factor analysis, descriptive statis

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Publication Date
Mon Sep 18 2023
Journal Name
Communications In Mathematical Biology And Neuroscience
Contribution of hunting cooperation and antipredator behavior to the dynamics of the harvested prey-predator system
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Fear, harvesting, hunting cooperation, and antipredator behavior are all important subjects in ecology. As a result, a modified Leslie-Gower prey-predator model containing these biological aspects is mathematically constructed, when the predation processes are described using the Beddington-DeAngelis type of functional response. The solution's positivity and boundedness are studied. The qualitative characteristics of the model are explored, including stability, persistence, and bifurcation analysis. To verify the gained theoretical findings and comprehend the consequences of modifying the system's parameters on their dynamical behavior, a detailed numerical investigation is carried out using MATLAB and Mathematica. It is discovered that the

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Publication Date
Sun Jun 24 2018
Journal Name
2018 Aiaa/ceas Aeroacoustics Conference
Mimicking the serration effects on aerofoil by leading edge blowing
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Publication Date
Sun Jun 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
The role of the learning organization in the behavior of the work teams \ exploratory research in the Rasheed Bank
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This research aims to examine the relationship between learning organization and behavior of work teams. The variable of the learning organization took four dimensions depending on the study (sudhartna & Li, 2004): Common cultural values ​​, communication, knowledge transfer and the characteristics of workers. The behavior of teams was identified on the basis of realizing of the respondents of their organization to work as a team where the research relied concepts applied in the study (Hakim , 2005) , and chose to research the case of a service organization for the study and relied on four dimensions of coordination , cooperation , sharing of information , the performance of the team, and was a curriculum approach and des

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Publication Date
Sun Jan 01 2023
Journal Name
Plasma Medicine
Thermal Effect of Laser on Silver Nanoparticles Synthesized by the Cold Plasma Method on Cancer Cells
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In this study, silver nanoparticles (AgNPs) were synthesized using a cold plasma technique and a plasma jet. They were then used to explore how photothermal treatment may be used to treat lung cancer (A549) and normal cells (REF) <i>in vitro</i>. The anti-proliferative activity of these nanoparticles was studied after A549 cells were treated with (AgNPs) at various concentrations (100&#37;, 50&#37;, or 25&#37;) and exposure times (6 or 8 min) of laser after 1 h or 24 h from exposed AgNPs. The highest growth inhibition for cancer cells is (75&#37;) at (AgNPs) concentration (100&#37;) and the period of exposure to the laser is (8 min). Particle size for the prepared samples varied according to the diameter o

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Publication Date
Sun Dec 01 2013
Journal Name
Baghdad Science Journal
The influence of Cinnamomum zeylanicum in plant tissue culture experiments of Gardenia jasmenoides Ellis
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Cinnamon plant is considered one of important medicinal plants because it is rich with many active compounds. This research is aimed to study possible effects of extract in culture media of Gardenia jasmenoides. Alcoholic extract was prepared from the bark of cinnamon at different concentrations (0.0, 1.0, 2.0) mg/L, then added to culture media to notice the effect of these concentrations on the growth and development of tissues and organs of Gardenia jasmenoides Ellis in vitro. Results showed the positive effect of increasing callus fresh weight and shoot proliferation from single nodes with presence of plant regulators, 5.0 mg/L Naphthalene acetic acid (NAA) and 3.0 mg/L Benzyl adenine (BA). Results showed that extract has a slight eff

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Publication Date
Fri Apr 01 2016
Journal Name
Journal Of Engineering
Effect of Variation of Degree of Saturation with depth on Soil–Concrete Pile Interface in Clayey Soil
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Bearing capacity of a concrete pile in fine grained cohesive soils is affected by the degree of saturation of the surrounding soil through the contribution of the matric suction. In addition, the embedded depth and the roughness of the concrete pile surface (expressed as British Pendulum Number BPN) also have their contribution to the shear strength of the concrete pile, consequently its bearing capacity. Herein, relationships among degree of saturation, pile depth, and surface roughness, were proposed as a mathematical model expressed as an equation where the shear strength of a pile can be predicted in terms of degree of saturation, depth, and BPN. Rel

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Publication Date
Sat May 01 2021
Journal Name
Civil Engineering Journal
The Suitability of Bailey Method for Design of Local Asphalt Concrete Mixture
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The study investigated the behaviour of asphalt concrete mixes for aggregate gradations, according to the Iraqi specification using the Bailey method designed by an Excel spreadsheet. In mixing aggregates with varying gradations (coarse and fine aggregate), The Bailey method is a systematic methodology that offers aggregate interlocking as the backbone of the framework and a controlled gradation to complete the blends. Six types of gradation are used according to the bailey method considered in this study. Two-course prepared Asphalt Concrete Wearing and Asphalt Concrete binder, the Nominal Maximum Aggregate Sizes (NMAS) of the mixtures are 19 and 12.5 mm, respectively. The total number of specimens was 240 for both layers (15 samp

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Publication Date
Wed Feb 12 2020
Journal Name
Journal Of Material Cycles And Waste Management
New application of eco-friendly biosorbent giant reed for removal of reactive dyes from water followed by sustainable path for recycling the dyes-loaded sludge in concrete mixes
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