In earthquake engineering problems, uncertainty exists not only in the seismic excitations but also in the structure's parameters. This study investigates the influence of structural geometry, elastic modulus, mass density, and section dimension uncertainty on the stochastic earthquake response of a multi-story moment resisting frame subjected to random ground motion. The North-south component of the Ali Gharbi earthquake in 2012, Iraq, is selected as ground excitation. Using the power spectral density function (PSD), the two-dimensional finite element model of the moment resisting frame's base motion is modified to account for random ground motion. The probabilistic study of the moment resisting frame structure using stochastic finite element utilizing Monte Carlo simulation was presented using the finite element program ABAQUS. The dynamic reliability and probability of failure of the stochastic and deterministic structure based on the first passage failure were checked and evaluated. Results revealed that the probability of failure increased due to randomness in stiffness and mass of the structure. Generally, natural frequencies for the lower modes of vibration and relative displacements for the lower stories were more sensitive to the randomness in system parameters.
Background: Denture fracture is one of the most common problems encountered by the patients and prosthodontists. The objective of present study was to evaluate the transverse strength of nylon denture base resin repaired by using conventional heat polymerized, autopolymerized and visible light cure {VLC} resins, surface treatment that used for repair and adjustment of insufficient nylon denture bases and in case of addition of artificial teeth. As these corrective procedures are common chair side procedures in dental clinic. Materials and methods: One hundred twenty nylon specimens were prepared by using metal patterns with dimension of (65x10x2.5 mm) length, width, and thickness respectively for transverse strength test while for tensile b
... Show MoreIn this research, a Co-polymer (Styrene / Allyl-2.3.4.6-tetra-O-acetyl-β-D-glucopyranoside) was synthesized from glucose in four steps using Addition Polymerization according to the radical mechanism using Benzoyl Peroxide (BP) as initiator. Initially, Allyl-2.3.4.6-tetra-O-acetyl-β-D-glucopyranoside monomer was prepared in three steps and the reaction was followed by (HPLC, FT-IR, TLC), in the fourth step the monomer was polymerized with Styrene and the structure was determined by FT-IR and NMR spectroscopy. The reaction conditions (temperature, reaction time, material ratios) were also studied to obtain the highest yield, the relative, specific and reduced viscosity of the prepared polymer was determined, from which the viscosity ave
... Show MoreCovalent modification of protein by drugs may disrupt self-tolerance, leading to lymphocyte activation. Until now, determination of the threshold required for this process has not been possible. Therefore, we performed quantitative mass spectrometric analyses to define the epitopes formed in tolerant and hypersensitive patients taking the β-lactam antibiotic piperacillin and the threshold required for T cell activation. A hydrolyzed piperacillin hapten was detected on four lysine residues of human serum albumin (HSA) isolated from tolerant patients. The level of modified Lys541 ranged from 2.6 to 4.8%. Analysis of plasma from hypersensitive patients revealed the same pattern and leve
ABSTRACT This study developed two adsorbents for extracting salbutamol sulphate (SAS) from water and urine samples after derivatisation with 2-aminobenzothiazole as a colour reagent. These adsorbents include cetylpyridinium chloride surfactant (CPC) modified silica and alumina-coated magnetite nanoparticles (Fe3O4/SiO2/CPC and Fe3O4/Al2O3/CPC). The derivatisation of SAS with the colour reagent resulted in an orange azo dye with maximum adsorption wavelengths of 443.0 nm. UV–Vis spectroscopy was used to identify the target analyte following the magnetic solid-phase extraction (MSPE) method. Under optimal conditions, the concentration ranges of 0.03–5.00 µg/mL and 0.05–6.00 µg/mL with good linearity (˃ 0.99), the detection limi
... Show MoreThe current research aims to identify the effect of the Bransford and Stein model on the achievement of fifth-grade literary students for geography and their reflective thinking. To achieve the objective of the research, the following two null hypotheses were formulated:
- There is no statistically significant difference at the significance level (0.05) between the average scores of the experimental group students who studied geography using the Bransford and Stein model and the average scores of the control group students who studied the same subject in the usual way in the achievement test. 2- There is no statistically significant difference at the significance level (0.05) between the average scores of the experimental gr
Bidentate Schiff base ligand 3-(3,4-Dihydroxy-phenyl)-2-[(4-dimethylamino-benzylidene)-amino]-2-methyl-propionic acid was prepared and characterized by spectroscopic techniques studies and elemental analysis. The Cd(II), Ni(II), Cu(II), Co(II), Cr(III),and Fe(III) of mixed-ligand complexes were structural explicate through Moler conductance , [FT-IR, UV-Vis & AAS], chloride contents, , and magnetic susceptibility measurements. Octahedral geometries have been suggested for all complexes. The Schiff base and its complexes were tested against various bacterial species, two of {gram(G+) and gram(G-)} were shown weak to good activity against all bacteria.
Low temperature and high relative humidity in the spring season led to decrease of field emergence ratio and growth in maize. Planting dates and seeds stimulation can be appropriate fix. Field experiment was conducted in the two spring seasons of 2022 and 2023. Randomize complete block design with split-plot arrangement and four replications was used. Planting date treatments (February 15th, March 1st and 15th and April 1st, 15th) were placed in main plots. Seeds stimulation treatments (potassium nitrate 6 mg L-1 + licorice extract 6 g L-1 as well as treatment of soaking with distilled water only) were placed in subplots. Seeds stimulation (potassium nitrate+licorice extract) or planting date of February 15th were superior at traits of fiel
... Show MoreThe study aimed to identify the importance of time in the Faculties of Physical Education and Sports Sciences atthe University of Baghdad, as well as to identify the relationship between time management and the level of staff functionalperformance. The research population consisted of the staff members who work in the Faculties of Physical Education andSports Sciences for Girls in Al-Jadriya for the academic year 2017-2018. A random sample of 50 staff members from eachfaculty were selected, that is the total number was (100) staff members. The researchers identified the concept of timemanagement and functional performance, after that a questionnaire consisting of (39) statements and (6) parts presented to aspecialized group of experts. The
... Show MoreBackground: Imaging techniques play a very important role in the specialty of endodontic. The ultrasonographic technique is non-expensive procedure, safe, and reproducible. The aim of the study was to determine the sensitivity, specificity, and accuracy of ultrasound and color Doppler ultrasonography in evaluation of periapical lesions (cyst, granuloma, mixed lesion “cyst within graulomas mass”, and abscess. Subject, Material and method: The sample consists of prospective study for 64 Iraqi participants who attended Karbalaa Specialized Center for Dentistry (males & females). Those patients were diagnosed clinically and radiographically as having periapical lesions of dental origin. They were examined by real time ultrasound and color
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