A ‘locking-bolt’ demountable shear connector (LBDSC) is proposed to facilitate the deconstruction and reuse of steel-concrete composite structures, in line with achieving a more sustainable construction design paradigm. The LBDSC is comprised of a grout-filled steel tube and a geometrically compatible partially threaded bolt. The latter has a geometry that ‘locks’ the bolt in compatible holes predrilled on the steel flange and eliminates initial slip and construction tolerance issues. The structural behaviour of the LBDSC is evaluated through nine pushout tests using a horizontal test setup. The effects of the tube thickness, strength of concrete slab, and strength of infilled grout on the shear resistance, initial stiffness, and ductility of the LBDSC are assessed. The experimental results show that the LBDSC can achieve higher shear resistance and similar initial stiffness as compared to traditional welded studs. In addition, all tested LBDSCs exhibited slip capacities ranging from 14 to 32 mm and can be classified as ductile shear connectors according to Eurocode 4. A detailed finite element model was also created and found to be reliable to reproduce the experimental behaviour. Parametric studies were subsequently conducted using the validated model to study further parameters and generalise the experimental results. Due to the specific test setup, non-negligible uplift forces were generated in the connector and the potential implications are discussed.
Pots experiment was conducted at the greenhouse of botanical garden belong to Department of Biology, College of Education for Pure Science, Ibn-AL-Haithum, University of Baghdad, for growth season 2018-2019. The aim of the experiment was to study the effects of foliar application of a-tocopherol concentrations (0, 50, 100, 150, 200 mg.L-1) on growth parameters and the activity of some antioxidant enzymes of wheat plant irrigated with sodium chloride concentrations (0, 75, 150, 225) mM.L-1. Salinity reduced plant growth parameter, plant height, flag leaf area, flag leaf chlorophyll content and increased the activity of antioxidant enzymes, superoxide dismutase and peroxidase. Plant growth parameters were enhanced by foliar application of a-t
... Show MoreThe study included selection six species of the fungi related to Pleurotus genus were evaluated for their ability to production of Pleurotin, one of them, Pleurotus ostreatus (P.11) was isolated and identified in the present study. Pleurotin was extracted with screening by Thin Layer Chromatography (TLC) and quantification High Performance Liquid Chromatography (HPLC). Cytotoxicity of Pleurotin extracted from P. ostreatus (P.11) grown in different sugar sources (galactose, mannitol, sucrose, dextrose and lactose) liquid media was test against three selected cancer cell lines, CaSki, MCF-7 and A549 addition to Human Non Cancer Fibroblast Cell Line (MRC-5). Pleurotin of P. ostreatus (P.11) grown in galactose induced the significant highest
... Show MoreThis study investigates the possibility of removing ciprofloxacin (CIP) using three types of adsorbent based on green-prepared iron nanoparticles (Fe.NPs), copper nanoparticles (Cu. NPS), and silver nanoparticles (Ag. NPS) from synthesized aqueous solution. They were characterized using different analysis methods. According to the characterization findings, each prepared NPs has the shape of a sphere and with ranges in sizes from of 85, 47, and 32 nanometers and a surface area of 2.1913, 1.6562, and 1.2387 m2/g for Fe.NPs, Cu.NPs and Ag.NPs, respectively. The effects of various parameters such as pH, initial CIP concentration, temperature, NPs dosage, and time on CIP removal were investigated through batch experiments. The res
... Show MoreIn this work, spinel ferrites (NiCoFe2O4) were prepared as thin films by dc reactive dual-magnetron co-sputtering technique. Effects of some operation parameters, such as inter-electrode distance, and preparation conditions such as mixing ratio of argon and oxygen in the gas mixture, on the structural and spectroscopic characteristics of the prepared samples were studied. For samples prepared at inter-electrode distance of 5 cm, only one functional group of OH- was observed in the FTIR spectra as all bands belonging to the metal-oxygen vibration were observed. Similarly, the XRD results showed that decreasing the pressure of oxygen in the gas mixture lead to grow more crystal planes in the samples prepare
... Show MoreThe theater has live foundations that interact with all symbols and signs. It has never been far from these innovations and developments in the manner of dealing with those symbols and how and the extent of their effects on society through the world of technology because the theatrical performance contributes to its structure, a technique that is employed by designers in various technologies such as ( Music, lighting and sound effects engineer, as well as fashion designer, architecture, and modeling designer). The theater today also relied on various interactive techniques represented in the use of body language and a sign in order to communicate the meaning by forming movements, singing and dancing in order for the recipient to interact
... Show MoreThis study illustrates effect of cold plasma CAP on the mineral blood components in vivo. the mineral blood component (Ca, Na, Cl, K and Fe) are used. Floating Electrode-Dielectric Barrier Discharge (FE-DBD) system of probe diameter 4cm is used for this purpose, and variable voltage (0-20) kV and variable frequency (0-30) kHz, the output power was ranged from (10 - 70) W. the effect of cold atmospheric plasma on mineral blood is studied with different exposure durations (30,45,60) sec. As the plasma exposure duration increases, the calcium, potassium and iron components in the blood increased, while The sodium and chlorine elements decreased. These results give an indication of the cold plasma receptor to be used to treat many disea
... Show MoreBackground: Controversy exists concerning the presence and amount of the Bennett mandibular immediate side shift among patients and whether it is necessary to accommodate for it in adjustable articulators. The aim of this study was to register and calculate the amount of any immediate side shift (ISS) present in patients requiring full mouth rehabilitation. Materials and methods: 3- dimensional condylar movements of 50 Iraqi TMD-free patients were recorded using a stereographic fully adjustable articulator system during protrusion, left and right eccentric mandibular movements. Protrusive angles of each patient were verified to figure out the suitable fossa analog for each case. The thickness of each right and left premade fossa analog sele
... Show MoreAnumerical solutions is presented to investigate the effect of inclination angle (θ) , perforation ratio (m) and wall temperature of the plate (Tw) on the heat transfer in natural convection from isothermal square flat plate up surface heated (with and without concentrated hole). The flat plate with dimensions of (128 mm) length × (64 mm) width has been used five with square models of the flat plate that gave a rectangular perforation of (m=0.03, 0.06, 0.13, 0.25, 0.5). The values of angle of inclination were (0o, 15o 30o 45o 60o) from horizontal position and the values of wall temperature (50oC, 60 oC, 70 oC, 90 oC, 100o<
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The study of oxygen mass transfer was conducted in a laboratory scale 5 liter stirred bioreactor equipped with one Rushton turbine impeller. The effects of superficial gas velocity, impeller speed, power input and liquid viscosity on the oxygen mass transfer were considered. Air/ water and air/CMC systems were used as a liquid media for this study. The concentration of CMC was ranging from 0.5 to 3 w/v. The experimental results show that volumetric oxygen mass transfer coefficient increases with the increase in the superficial gas velocity and impeller speed and decreases with increasing liquid viscosity. The experimental results of kla were correlated with a mathematical correlation des
... Show MoreBackground: Multidrug-resistant (MDR) enterococci have become a major problem in recent times and have been reported increasingly around the world. Lytic phages infect bacteria leading to rapid host death with limited risk of phage transduction, underlining the increasing interest in potential phage therapy in the future. Objective (s): The aim of this study is to use phage therapy as alternative approach for treatment of Enterococcus faecalis infections that recorded as MDR in Iraq to tackle this problem. Materials and Methods: Thirty E. faecalis isolates were collected from patients with different infectious diseases such as urinary tract infection (UTI), diabetic foot, septicemia, and wound infections. The isolation of specific l
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