The aim of this study is to determine the level of pollution with heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) and their potential sources in dust samples collected from schools in Ramadi City, Iraq. The dust samples were collected from 40 primary schools and two kindergartens and analyzed by using atomic absorption spectrophotometer. The heavy metal concentrations were found to follow the order Cr > Cu > Pb > Ni > Zn > Cd. The results indicated that the concentrations of Cd, Cu, and Pb exceeded the permitted background values. The pollution level was assessed using the geo-accumulation index (Igeo) and pollution load index (PLI). The classification of dust samples according to Igeo values showed that they ranged from unpolluted for Cu, Cr, Ni, and Zn, to moderately polluted for Pb, and heavily polluted for Cd. The PLI values indicated no to moderate pollution load. The results of the comparisons of heavy metal concentrations with the background values, as well as the multivariate statistical analysis, indicated three groups of heavy metals with different sources or origins: (1) Cd and Cu (anthropogenic source: vehicle emissions); (2) Pb (mixed source); and (3) Cr, Ni, and Zn (Geogenic source). This study is the first attempt in Iraq to investigate the concentrations of heavy metals in the dust of indoor environments. This study provides the environmental protection managers and decision-makers with important information about the concentrations of heavy metals and their sources in indoor environments.
Aluminum alloys widely use in production of the automobile and the aerospace because
they have low density, attractive mechanical properties with respect to their weight, better
corrosion and wear resistance, low thermal coefficient of expansion comparison with traditional
metals and alloys. Recently, researchers have shifted from single material to composite materials
to reduce weight and cost, improve quality, and high performance in structural materials.
Friction stir processing (FSP) has been successfully researched for manufacturing of metal
matrix composites (MMCs) and functional graded materials (FGMs), find out new possibilities
to chemically change the surfaces. It is shown th
This research is mostly concerned of exploration analysis of a random sample of data from Al-sadder hospital. We examine duration of hospital stay (DHS) and investigate any significant difference in duration between sex, age groups, occupation, patients’ condition at admission, and patients’ condition at discharge
This research is considered as the beginning of other studies about the iraqi the public and their relationship with the various state institutions. Recently, such studies used to be almost non-existent. The main characteristic that distinguishes the scientific studies, is the fact that it involves a specific problem that needs to be studied and analysed from multiple aspects, otherwise the definition of problem identification wouldn’t have been narrowing the topic into what the researcher wants to address, also not what the title is referring to as topics which the researcher doesn’t want to address. The problem in this research resides in the lack of well planned scientific programs that aims at building a positive mental picture a
... Show MoreLaurylamine hydrochloride CH3(CH2)11 NH3 – Cl has been chosen from cationic surfactants to produce secondary oil using lab. model shown in fig. (1). The relationship between interfacial tension and (temperature, salinity and solution concentration) have been studied as shown in fig. (2, 3, 4) respectively. The optimum values of these three variables are taken (those values that give the lowest interfacial tension). Saturation, permeability and porosity are measured in the lab. The primary oil recovery was displaced by water injection until no more oil can be obtained, then laurylamine chloride is injected as a secondary oil recovery. The total oil recovery is 96.6% or 88.8% of the residual oil has been recovered by this technique as shown
... Show MoreIn this work, the photoluminescence spectra (PL) of porous silicon (PS) have been modified by adding gold nanoparticles (AuNPs) to PS layer. PS was produced via Photo electro-chemical etching (PECE) method of n-type Si wafer with resistivity of about (10 Ω.cm) and (100) orientation. Laser wavelength of (630 nm) and illumination intensity of about (30 mW/cm2), etching current density of (10mA/cm2), and etching time of (4 min) were used during the etching process. The bare PS before metallic deposition process and porous silicon/gold nanoparticles (PS/AuNPs) structures were investigated by X-Ray Diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-Ray (EDX). The photoluminescence spectra were investigated as a fu
... Show MoreNanofluids, liquid suspensions of nanoparticles (NPs) dispersed in deionized (DI) water, brine, or surfactant micelles, have become a promising solution for many industrial applications including enhanced oil recovery (EOR) and carbon geostorage. At ambient conditions, nanoparticles can effectively alter the wettability of the strongly oil-wet rocks to water-wet. However, the reservoir conditions present the greatest challenge for the success of this application at the field scale. In this work, the performance of anionic surfactant-silica nanoparticle formulation on wettability alteration of oil-wet carbonate surface at reservoir conditions was investigated. A high-pressure temperature vessel was used to apply nano-modification of oil-wet
... Show MoreA metal-assisted chemical etching process employing p-type silicon wafers with varied etching durations is used to produce silicon nanowires. Silver nanoparticles prepared by chemical deposition are utilized as a catalyst in the formation of silicon nanowires. Images from field emission scanning electron microscopy confirmed that the diameter of SiNWs grows when the etching duration is increased. The photoelectrochemical cell's characteristics were investigated using p-type silicon nanowires as working electrodes. Linear sweep voltammetry (J-V) measurements on p-SiNWs confirmed that photocurrent density rose from 0.20 mA cm-2 to 0.92 mA cm-2 as the etching duration of prepared SiNWs increased from 15 to 30 min. The
... Show MoreCopper, and its, alloys and composites (being the matrix), are broadly used in the electronic as well as bearing materials due to the excellent thermal and electrical conductivities it has.
In this study, powder metallurgy technique was used for the production of copper graphite composite with three volume perc ent of graphite. Processing parameters selected is (900) °C sintering temperature and (90) minutes holding time for samples that were heated in an inert atmosphere (argon gas). Wear test results showed a pronounced improvement in wear resistance as the percent of graphite increased which acts as solid lubricant (where wear rate was decreased by about 88% as compared with pure Cu). Microhardness and
... Show MoreBackground:Wilson’s disease (WD) is an inherited
disorder of copper metabolism that is characterized
by tremendous variation in the clinical presentation.
Objective: To assess demographic distribution,
clinical presentations, diagnostic evaluation, and any
association between clinical presentations and other
studied variables of a sample of Iraqi patients with
WD.
Methods: A descriptive cross sectional study with
analytic elements was conducted during 2011, from
the 1st of February till the 10th of June. The sampling
method was a convenient non-random one, carried
out through consecutive pooling of registered WD
patients. A questionnaire-form paper had been
developed for the process of data col
The semantic analysis is characterized by its ability to describe the communicative pattern and its high efficiency in questioning its semantic manifestations and its deliberative purposes, which helped to understand the symbolic, contextual and cultural manifestations of the structure of the pattern, whether verbal or nonverbal. In order to highlight the role of the semiautomatic approach and its application to a sample of slogans collected from "media, social networking sites, in-kind views, media institutions, etc." to study the components and analyze the contents and highlight the signs. His boat logo is not just uttered as a linguistic transmission of a message, but as a political Tghieria actually . For example, the slogan "People Wan
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