This paper aims to investigate the flexural behavior of reinforced concrete beams considering fire resistance by adding Lightweight Expanded Clay Aggregates (LECA) to the concrete mix as partial coarse aggregate replacement. LECA is a type of porous clay with a uniform pore structure with fine, closed cells and hard, tightly sintered skin. The experimental work comprised four reinforced self-compacted concrete beams. All the specimens were identical in their geometrical layout of 1600×240×200 mm, reinforcement details, and support condition (simply supported). For all the beams, the main reinforcement was provided by two bars, each having a diameter of 12 mm, while a bar of 6 mm diameter was employed for the top and shear reinforcement. Each beam had a different replacement ratio of LECA for coarse aggregates (0, 10, 20, and 30%). All the specimens were tested under static two concentrated loads after being exposed to the fire of steady-state temperature (500 oC), 1 hr duration, and sudden cooling process. The results showed that adding LECA reduced the number and width of the generated cracks due to fire and reduced the deterioration of the ultimate load capacity and beam rigidity (stiffness).
In this research, we studied the effect of concentration carriers on the efficiency of the N749-TiO2 heterogeneous solar cell based on quantum electron transfer theory using a donor-acceptor scenario. The photoelectric properties of the N749-TiO2 interfaces in dye sensitized solar cells DSSCs are calculated using the J-V curves. For the (CH3)3COH solvent, the N749-TiO2 heterogeneous solar cell shows that the concentration carrier together with the strength coupling are the main factors affecting the current density, fill factor and efficiency. The current density and current increase as the concentration increases and the
Background: Healing of a tooth extraction socket is a complex process involving tissue repair and regeneration. It involves chemotaxis of appropriate cells into the wound, Transformation of undifferentiated mesenchymal cells to osteoprogenitor cells, proliferation and differentiation of committed bone forming cells, extracellular matrix synthesis, mineralization of osteoid, maturation and remodeling of bone. These cellular events are precisely controlled and regulated by specific signaling molecules. Some of these like transforming growth factor beta (TGF-?), vascular endothelial growth factor (VEGF), bone morphogenetic proteins (BMP) and insulin like growth factors (IGF) are well conserved proteins involved in the initial response to injur
... Show MoreThe study aimed to determine the impact of energy for the north and south magnetic poles on the the growth of bacteria isolated from cases of tooth decay, 68 swabs were collected from surfaces of faulty tooth, the detected of Staphylococcus aureus
... Show MoreBackground: Odontogenisis is a complex process controlled by dynamic and reciprocal interactions that regulated by various molecules. Thymosin β4 is a small bioactive peptide with wide spectrum biological effects on much cell types. The present study was designed to highlight the effect of synthetic exogenous Tβ4 on developing dental tissue of the upper central teeth of rats, by histological examination and immunohistochemical evaluation of TGFβ1. Materials and method: Thirty six Albino Wister pregnant rat 18control group received intraperitoneal injection of normal saline and the others are experimental group received 50µg/300µl of Tβ4 injection. The animals were sacrificed at periods 16th and 18th day I.U.L and one day p
... Show MoreThe current study was conducted to evaluate the effect a mixture of threespecies of arbuscular mycorrhizal fungi (Glomus etunicatum, G. leptotichum andRhizophagus intraradices) double and triple mixture and organic matter by usingplastic pots in the greenhouse at some mycorrhiza and physiological limitationscharacteristics in tomato plant after four and eight weeks of cultivation. Theresults of the determinants mycorrhiza significant increase the percentage ofmycorrhizal frequency F% dry weight of roots mycorrhiza (g.plant-1) andorganic matter in all mycorrhiza single, double and triple mixture after four andeight weeks cultivation treatments. The highest percentage of mycorrhizalfrequency and increase the dry weight of the root in the trea
... Show MoreThis research was carried out in quail in the laboratory of histopathology diseases during four months. The objectives of this study was to detecting the effects of the addition of the alcohol extract of ginger to ovary tissue of quail. The two groups of birds were in almost similar weights and were placed in cages. Each group consisted of 8 quails. The first group (control group) fed on regular feeding without adding alcoholic extract of ginger. The second group (treated group) fed on the same normal food after adding the alcohol extract of ginger at a concentration of 300 mg / kg. The results indicated that ginger have positive effects on folliculogenesis.
he current research aims to determine the extent of interest of the Oil Products Distribution Company (OPDC) and its various departments in the process of strategic foresight (SF), and the extent of interest that is reflected in the achievement of strategic leadership (SE). As well as knowing the nature of the relationship and the impact on the company. To achieve the objectives of the research, one main hypothesis was formulated, and three sub-hypotheses emerged from it. As the research relied on an analytical survey approach, the research targeted the workers within this company, And he reached a set of results, based on which a number of conclusions were formulated. The research community consisted of (185) individuals, and (160)
... Show MoreThe research is concerned about studying the absorption spectrum of the solution coumarin dye C47. The chloroform solvent was used with C47 dye in three different concentrations 10-4, 10-5 and 10-6 M. The laser dye solution was prepared by dissolving the required amount of dye in chloroform alcohol, while studying absorption spectrum before and after irradiation with gamma ray by cobalt-60 source 60Co at exposure time, which are 0, 4, 6 and 18 hours with different absorbed doses 0, 136, 204 and 612 Gy. The results show that red shift in the absorption spectrum was increased by increasing the concentration of laser dye solutions , while the increase of gamma dose led to increase the red shift after irradiation, as the exposure period and irr
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