In this study, derivatives of polyvinyl alcohol (PVA) grafted with phthalic anhydride (PhA) and dyes were prepared to produce polymeric materials of PVA-g-PhA, PVA-g-PhA-anthocyanin, PVA-g-PhA-bromophenol blue, and PVA-g-PhAthymol blue. The materials were characterised by FTIR and 1 H NMR spectroscopies. The crystallinity of the polymers was evaluated with powder X-ray difraction, and the thermal stability by thermogravimetric analysis (TGA). The synthetic procedure for the polymeric materials entailed the formation of esters. The FTIR spectra of the polymers confrmed their formation since the ester carbonyl group stretch was observed at approximately 1691–1716 cm−1 in each material. NMR spectroscopy confrmed the addition of the dyes to the PVA-g-PhA backbone. All the powder X-ray difractograms displayed the characteristic peak for PVA at a 2θ value of approximately 20°, as well as a small peak at 42° indicative of the semicrystalline nature of the samples. These difractograms indicate a small degree of crystallinity in a mainly bulk amorphous phase. Adding dyes to PVA-g-PhA improved the thermal stability of the resulting polymers. The PVA-g-PhA-bromophenol blue material was the most thermally stable. The absorption properties of PVA-g-PhA were extended into the visible region by the attachment of the dyes. The photostability of the polymers was investigated by irradiating them with 254 nm light. The absorbance of the parent material, PVA-g-PhA, and the anthocyanin derivative increased with irradiation time until it reached a photostationary state. This increase in absorbance is attributed to the formation of more conjugated structures or light-absorbing photoproducts. On the other hand, the PVA-g-PhA-bromophenol blue and PVA-g-PhA-thymol blue materials photodegraded with increasing irradiation time. This research has shown that grafting dyes onto PVA can improve thermal stability and extend light absorption into the visible region. In particular, the addition of anthocyanin dye improved the photostability of the resulting material.
Background: Accurate measurement of a patient’s height and weight is an essential part of diagnosis and therapy, but there is some controversy as to how to calculate the height and weight of patients with disabilities. Objective: This study aims to use anthropometric measurements (arm span, length of leg, chest circumference, and waist circumference) to find a model (alternatives) that can allow the calculation of the height and the body weight of patients with disabilities. Additionally, a model for the prediction of weight and height measurements of patients with disabilities was established. Method: Four hander patients aged 20-80 years were enrolled in this study and divided into two groups, 210 (52.5%) male and 190 (47.5%) fe
... Show MoreA new class of higher derivatives for harmonic univalent functions defined by a generalized fractional integral operator inside an open unit disk E is the aim of this paper.
The [2-aminobenzothiazole]was reacted with [2,4,6 triyhydroxy-acetophenon monohydrate] to give a new ligand [2-N-2,4,6-trihydroxyacetophenonyliden benzothiazole] [H3L]. This ligand was reacted with metal ions ( CoII, NiII,CuII and ZnII) in methanol as solvent with ( 1:2 ) metal : ligand ratio to give a series of new complexes with general formula [ M(H2L)2],(where:M= CoII, NiII ,CuIIand, ZnII).All compounds were characterized by spectroscopic methods ( I.R , U.V – vis,HPLC) atomic absorption, along with chloride content and conductivity measurements. According to the data of these measurements we suggested a tetrahedral
A low speed open circuit wind tunnel has been designed, manufactured and constructed at the Mechanical Engineering Department at Baghdad University - College of Engineering. The work is one of the pioneer projects adapted by the R & D Office at the Iraqi MOHESR. The present paper describes the first part of the work; that is the design calculations, simulation and construction. It will be followed by a second part that describes testing and calibration of the tunnel. The proposed wind tunnel has a test section with cross sectional area of (0.7 x 0.7 m2) and length of (1.5 m). The maximum speed is about (70 m/s) with empty test section. The contraction ratio is (8.16). Three screens are used to minimize flow disturbances in the test section.
... Show MoreThis study investigates the characterization and mechanical performance of Stone Mastic Asphalt (SMA) mixtures modified with two types of polymers: styrene–butadiene–styrene (SBS) and high-molecular-weight polyethylene (PE). Neat asphalt cement PG 64-16 was modified using a higher content of SBS and PE at concentrations of 6%, 7%, and 8% by weight of asphalt through the dry blending method to produce Highly Modified Asphalts (HiMA). The physical and rheological properties of the modified binders were evaluated using penetration, softening point, rotational viscosity, and dynamic shear rheometer (DSR) tests. Also, their phase compatibility and morphological changes were evaluated using the storage stability testing and scanning electron
... Show MoreBackground: The denture base inaccuracies during processing negatively influence the retention and stability of finished complete denture. The aims of this study were to evaluate teeth movement and palatal adaptation of autoclave cured denture bases and their relationship with palatal depths and investments. Materials and methods: A nightly maxillary complete dentures prepared, processed and organized to be tested as follows: 1. Processing methods: water bath and autoclave with both fast and slow cycles. 2. Palatal depth: shallow, medium and deep. 3. Investing medium: stone and silicone. For every finished denture, two measurements were done: first: teeth movement by attaching metallic reference screws on the right and left centrals, first
... Show MoreThe effect of air injection device on the performance of airlift pump used for water pumping has been studied numerically and experimentally. An airlift pump of dimensions 42mm diameter and 2200 mm length with conventional and modified air injection device was considered. A modification on conventional injection device (normal air-jacket type) was carried out by changing injection angle from 90 (for conventional) to 22.5 (for modified). Continuity and Navier-Stokes equations in turbulent regime with an appropriate two-phase flow model (VOF) and turbulent model ( ) in two dimensions axisymmetry flow were formulated and solved by using the known package FLUENT version (14.5). The numerical and experimental investiga
... Show MoreThispaperpresentsthesynthesisandstudyofsomenewmixed-liagnd complexescontainingtowaminoacids[Alanine(Ala)andphenylalanine(phe)]withsome metals .Theresultsproductswerefoundtobesolidcrystallinecomplexeswhichhave been characterized by using (FT-IR,UV-Vis) spectra , melting point, elemental analysis (C.H.N) , molar conductivity and solubiltyThe proposed structure of the complexes using program , chem office 3D(2000) .The general formula have been given for the prepared complexes :[M(A-H)(phe-H)]M(II): Hg , Mn ,Co , Ni , Cu ) , Zn , Cd(II) .Ala = Alanine acid = C3H7NO2Phe = phenylalanine = C9H11NO2