Crab shells were used to produce chitosan via the three stages of deproteinization, demineralization and deacetylation using sodium hydroxide and hydrochloric acid under different treatment conditions of temperature and time. The produced chitosan was characterized using Fourier transform infrared spectroscopy (FTIRS), X-ray diffraction (XRD), high – resolution scanning electron microscopy (HRSEM), electron dispersion spectroscopy (EDS), dynamic light scattering (DLS), Brunauer Emmett Teller (BET) and Thermogravimetric analysis (TGA). The adsorption behavior of chitosan to remove arsenic (As) and copper (Cu) from electroplating wastewater was examined by batch adsorption process as a function of adsorbent dose, contact time and temperature. The FTIR, XRD, HRSEM and EDS analyses confirmed, respectively, the presence of –NH2 and –OH functional groups, with amorphous/crystalline phases, crystallinity index of 69.54%, needle-like morphology and Carbon (C), Oxygen (O) and Nitrogen N) in the produced chitosan. While DLS, BET and TGA showed, respectively, that the produced chitosan has an average particle size of 729nm, is moderately polydisperse, has12.67 m2/g surface area, mesoporous in nature, and with thermal stability of up to 1430C. The optimum adsorbent dose, contact time and temperature values to remove As and Cu by chitosan were 15mg, 45 minutes, 333K and25mg, 60 minutes, 349K,respectively. Under the employed conditions, chitosan though has a low surface area, displaying high adsorption capacity for both metal ions. The adsorption isotherm data were better fitted to the Jovanovic isotherm model while the kinetic data fitted best to the pseudo-second order model. The thermodynamic studies established that the adsorption was feasible but endothermic in nature. This study shows that chitosan adsorbents purify electroplating wastewater.
The technology and modern social communication medias have contributed to changing many of our concepts about education to a large extent; these technological advancements have created new challenges for the Instructor of course, but on the other hand it did provided him with expressive media, models and strategies that the old methods cannot fulfill, including the flipped classroom strategy, which is one of the modern technical solutions and in it's optimal use it can correct the weakness of the traditional education and can develop the communication skills as a whole among the students, in order to create a positive, active and interactive student.
The current research contained - four chapters: the first one included the methodolog
: The Aluminium (Al) material emerged as a plasmonic material in the wavelength ranges from the ultraviolet to the visible bands in different on-chip plasmonic applications. In this paper, we demonstrate the effect of using Al on the electromagnetic (EM) field distribution of a compact hybrid plasmonic waveguide (HPW) acting as a polarization rotator. We compare the performance of Al with other familiar metals that are widely used as plasmonic materials, which are Silver (Ag) and Gold (Au). Furthermore, we study the effect of reducing the geometrical dimensions of the used materials on the EM field distributions inside the HPW and, consequently, on the efficiency of the polarization rotation. We perform the study based o
... Show MoreTax state institution regards as one of the largest state institutions implementing the tax rules issuing be legislative body and achieving the goals of tax (financial, economic, social and political). So, the tax management should pay attention to the procedures enabling it to achieve those rules starting from the procedures of tax restrict and ending by tax allocation where the process of assessment the taxation must relaxing on modern methods. The problem of the study raising from that in spite of there is a low obliging the taxable person (registered or not) to submit a declaration about his income and the achieved profit to be the base of taxation˒ where the other ways are secondary ways helping in rejection of t
... Show MoreNumerical investigation has been carried out on heat transfer and friction factor characteristics of copper-water nanofluid flow in a constant heat-fluxed tube with the existence of new configuration of vortex generator using Computational Fluid Dynamics (CFD) simulation. Two types of swirl flow generator: Classical twisted tape (CTT) and Parabolic-cut twisted tape (PCT) with a different twist ratio (= 2.93, 3.91 and 4.89) and different cut depth (= 0.5, 1.0 and 1.5 cm) with 2% and 4% volume concentration
... Show MoreDeconstruction is an intellectual stream that emerged as a result of the changes and requirements of the modern era. This stream extended from thought and literature to all arts, and the research included four chapters.
Chapter One: From the research, the research problem was identified in the form of a question: Have the ideas and deconstructive concepts represented in the abstract drawings of the artist Shaker Hassan Al Said?
The importance and limits of the research were reviewed and the goal of the research was to reveal the applications of ideas and deconstructive concepts in the abstract drawings of the artist Shaker Hassan Al Said, in addition to defining the most important terms contained in it.
Chapter Two: Previous
Abstract
Background and objective: Protective effect of (Andrographis Paniculata) on 4-Vinylcyclohexene Diepoxide.
Material and methods:A group of 55 female albino rats undergo experiment on the outcome effect of 4-vinylcyclohexene Diepoxide injection for a priod of two weeks, as well as treatment effect of methanolic leaf extract of Andrographis paniculata oral administration for four weeks. Injection concentrations (160 and 320mg/kg. B.W) also two different doses of treatment (100 and 200mg/kg. B.W) have been applied.
Results:The results on body weight and ovary weight were more evident when higher concentration dose was applied.
... Show MoreObjective: The study aims to determine the effectiveness of the continuing nursing education
program on nursing staffs knowledge in kidney transplantation unit and to find out the relationship
between nursing staffs knowledge and demographic characteristics (age, gender, education level, and
years of experiences in kidney transplantation unit).
Methodology: A quasiexperemental design (One-group Pretest - Posttest design) was carried out in
kidney transplantation units at Baghdad Teaching Hospitals, from December 2011 to July 2012. A nonprobability
(purposive sample) of (16) nurses were selected from kidney transplant units at Baghdad
teaching hospitals, the choice was based on the study criteria. The data were collec