Straight tendons in pretensioned members can cause high-tensile stresses in the concrete extreme fibers at end sections because of the absence of the bending stresses due to self-weight and superimposed loads and the dominance of the moment due to prestressing force alone. Accordingly, the concrete tensile stresses at the ends of a member prestressed with straight tendons may limit the service load capacity of the member. It is therefore important to establish limiting zone in the concrete section within which the prestressing force can be applied without causing tension in the extreme concrete fibers. Two practical methods are available to reduce the stresses at the end sections due to the prestressing force. The first method based on changing the eccentricity of some tendons by raising them towards the end zone. The second method is based on bond prevention by encasing some of the tendons in plastic sheathing, effectively moving the point of application of prestressing force inward toward midspan for part of tendons. The present study focuses on a proposed third method to reduce the effect of the prestressing force near end supports by using straight strands with limited initial prestressing value in compression zone. New equations were suggested for the cracking moment and the prestressing force which consider the prestressed tendons in compression zone.
In this work, the effect of annealing temperature on the electrical properties are studied of p-Se/ n-Si solar cell, which p-Se are deposit by DC planar magnetron sputtering technique on crystal silicon. The chamber was pumped down to 2×10−5 mbar before admitting the gas in. The gas was Ar. The sputtering pressure varied within the range of 4x10-1 - 8x10-2mbar by adjusting the pumping speed through the opening control of throttle valve. The electrical properties are included the C-V and I-V measurements. From C-V measurements, the Vbi are calculated while from I-V measurements, the efficiency of solar cell is calculated.
Background: Pumpkin seeds are a valuable source of high-quality protein and can be utilized as functional food ingredients due to their properties, such as solubility, foam formation, and stability. This study aims to produce protein isolate and its enzymatic hydrolysates from local pumpkin seeds to study their properties. Methodology: Preparing defatted pumpkin seeds for protein extraction, followed by the enzymes’ hydrolysis using Trypsin and Pepsin enzymes separately and together in two methods. The determination of amino acids and the degree of hydrolysis was conducted; moreover, protein properties were studied, including solubility, emulsifying activity, stability index, foaming capacity, and stability. Results: A protein sample was
... Show MoreThe antagonism of the rhizospheric bacteria toward pathogenic fungi Macrophomina phaseolina was investigated. Ten soil samples were collected from the rhizospheric zone around Cowpea root (Vignaunguiculata L.). These samples were used as the source of Arbuscular Mycorrhizal fungi (AMF) and rhizobacterial isolates. Twenty-five bacteria were isolated and evaluated as an antagonistic agent against pathogenic fungi. M. phaseolina was isolated from infected roots of Cowpea and used as a pathogen. Twenty-five bacteria were isolated and evaluated as an antagonistic agent against pathogenic fungi. M. phaseolina was isolated from infected roots of Cowpea and used as a pathogen. The synergistic effect between A. siccitolerans and (AMF) Glomusmosseae,
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Our description of the wxperience of any poet depends on the nature the anture of his writing or his style in terms of factors affecting his experience . We have found that al- Maghout is characterized by important poetis properties that characterized all of his poetry such as the ease in compositions that are formed the vocabulary of daily life . This is what constitutes his poetic lexicon that depends on the vocabulary of space , time , and anture . Hispoetry derives its aesthetics from revealing that strains in the text for the sake of surprise and amazement with a simple realism.
In this research, the dynamics process of charge transfer from the sensitized D35CPDT dye to tin(iv) oxide( ) or titanium dioxide ( ) semiconductors are carried out by using a quantum model for charge transfer. Different chemical solvents Pyridine, 2-Methoxyethanol. Ethanol, Acetonitrile, and Methanol have been used with both systems as polar media surrounded the systems. The rate for charge transfer from photo-excitation D35CPDTdye and injection into the conduction band of or semiconductors vary from a to for system and from a to for the system, depending on the charge transfer parameters strength coupling, free energy, potential of donor and acceptor in the system. The charge transfer rate in D35CPDT / the syst
... Show MoreAs major nosocomial pathogens,
In this study, 20