This study deals with the serviceability of reinforced concrete solid and perforated rafters with openings of different shapes and sizes based on an experimental study that includes 12 post-fire non-prismatic reinforced concrete beams (solid and perforated). Three groups were formed based on heating temperature (room temperature, 400 °C, and 700 °C), each group consisting of four rafters (solid, rafters with 6 and 8 trapezoidal openings, and rafter with eight circular openings) under static loading. A developed unified calculation technique for deflection and crack widths under static loading at the service stage has been provided, which comprises non-prismatic beams with or without opening exposed to flexure concentrated force. Two approaches were used to compute the deflection: The first attempt was conducted by using the moment of inertia for solid non-prismatic beam and reduced for those with openings by the ratio of residual rafter self-weight. The second was performed by using the moment of inertia of transformed cracked sections depending on the segmental rafter method. The crack width was determined using the ACI code's equation. The analytical and experimental results were evaluated and found to be in good agreement.
Due to the low cost of both unsaturated polyester resin and the plant fibers along with protect of the environment, the wasted Carrot fibers were employed in this study to strengthen and color the resin. Carrot peels powders have been incorporated with unsaturated polyester/ natural fibers (UPE/C.F) gel coats to form a good candidate with good mechanical behaviors in different industrial applications. The wasted carrot peels fibers, were dried, crashed and milled into micro particles sizes (2.5% microns) to improve the mechanical properties (impact energy, Compressive load and Elastic Modulus) of unsaturated polyester. Micro carrot fibers (C.F) have been loaded to unsaturated fibers a
This paper presents a grey model GM(1,1) of the first rank and a variable one and is the basis of the grey system theory , This research dealt properties of grey model and a set of methods to estimate parameters of the grey model GM(1,1) is the least square Method (LS) , weighted least square method (WLS), total least square method (TLS) and gradient descent method (DS). These methods were compared based on two types of standards: Mean square error (MSE), mean absolute percentage error (MAPE), and after comparison using simulation the best method was applied to real data represented by the rate of consumption of the two types of oils a Heavy fuel (HFO) and diesel fuel (D.O) and has been applied several tests to
... Show More(E)-2-(benzo[d]thiazol-2-yliazenyl)-4-methoxyaniline was synthesized by reaction the diazonium salt of 2-aminobenzothiazole with 4-methoxyaniline. Identified of the ligand by spectral techniques (UV-Vis, FTIR,1HNMR and LC-Mass) and microelemental analysis (C.H.N.S.O) are used to produce of the azo ligand. Complexes of (Co2+, Ni2+, Cu2+ and Zn2+) were synthesized and identified using atomic absorption of flame, elemental analysis, infrared and UV-Vis spectral process as well conductivity and magnetic quantifications. Nature of compounds produced have been studied followed the mole ratio and continuous contrast methods, Beer's law followed during a concentration scope (1×10-4-3×10-4 mole/L). height molar absorptivity of compound solutions h
... Show MoreCeliac disease (CD) is the most common genetically - based disease in correlation with food intolerance. The aim of this study is to measure the activity of ALT enzyme and purify enzyme from sera women with celiac disease. Alanine aminotransferase (ALT) activity has been assayed in (30) women serum samples with celiac disease, age range between (20-40) year and (30) serum of healthy women as control group, age range between (22-38) year. In the present study, the mean value of ALT activity was significantly higher in patients with celiac disease than healthy group (p<0.01). The ALT enzyme was partial purified from sera women with celiac disease by dialysis, gel filtration using Sephadex G- 50 and ion exchange chromatography using DEAE- cell
... Show MoreHypothyroidism is a frequent disorder in the general population, especially among women, is defined as adeficiency of thyroid activity that results from insufficient production or action of thyroid hormones leading to a totaldecrease of metabolic. Human leukocyte antigen is the most polymorphic genetic system in man. Genes of this regioninfluence susceptibility to certain diseases.Objectives: The purpose of the present study is to investigate the role of HLA-DRB1 genotyping in hypothyroidpatients with and without periodontitis. Sixty hypothyroid patients 30 of patients were with periodontitis and 30without periodontitis compare with 30 healthy subjects as control enrolled in this study. DNA was extracted fromblood samples, then HLA- genotyp
... Show MoreThis work studied the electrical and thermal surface conductivity enhancement of polymethylmethacrylate (PMMA) clouded by double-walled carbon nanotubes (DWCNTs) and multi-walled carbon nanotube (MWCNTs) by using pulsed Nd:YAG laser. Variable input factors are considered as the laser energy (or the relevant power), pulse duration and pulse repetition rate. Results indicated that the DWCNTs increased the PMMA’s surface electrical conductivity from 10-15 S/m to 0.813×103 S/m while the MWCNTs raised it to 0.14×103 S/m. Hence, the DWCNTs achieved an increase of almost 6 times than that for the MWCNTs. Moreover, the former increased the thermal conductivity of the surface by 8 times and the later by 5 times.
Background: Contact between implant material and bones must be strong and fast creation, to fulfill these properties appropriate surface modifications must apply on used implants. In this contribution; double surface modifications are applied on Ti-6Al-4V alloy to accelerate osseointegration. Materials and methods: Anodic process is utilized to create titania nanotubes (TNTs) on the screws made from Ti-6Al-4V alloy. These implants were coated with nano ZrO2 particles. Second modification was annealing anodized screws at 8000C, and implanted in tibiae of nine adult New Zealand white rabbits. Results: Physical and histological consequences of two surface modifications on Ti-6Al-4V alloy screws were studied. Scanning electron microscope (SEM)
... Show MoreIt is suitable to use precast steel-concrete composite beams to quickly assemble a bridge or a building, particularly in isolated regions where cast-in-situ concrete is not a practical option. If steel-concrete composite beams are designed to allow demountability, they can also be extremely useful in the aftermath of natural disasters, such as earthquakes or flooding, to replace damaged infrastructure. Furthermore, rapid replacement of slabs is extremely beneficial in case of severe deterioration due to long-term stressors such as fatigue or corrosion. The only way to rapidly assemble and disassemble a steel-concrete composite structure is to use demountable shear connectors to connect/disconnect the steel beams to/from the concrete slab. I
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