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Effect Of Ultra-Fine Limestone On The Physico-Mechanical Properties Of Cement Pastes, M. Saraya, M. Tantawy, M. Taher
Effect Of Ultra-Fine Limestone On The Physico-Mechanical Properties Of Cement Pastes, M. Saraya, M. Tantawy, M. Taher
Al-Azhar Bulletin of Science
The aim of the present work is to study the effect of limestone and ultra-fine limestone fillers on the physico-mechanical properties of hardened cement pastes. The particle size distribution was determined by laser diffractometer and SEM as well as the mineralogical composition by X- Ray Diffraction (XRD) and Fourier transform Infrared (FT-IR). The OPC was replaced with limestone filler up to 15wt% as well as ultra-fine limestone to form eight mixes. The hydration characteristics of hydrated cement pastes were evaluated by measuring the combined water content, bulk density and compressive strength up to 90 days as well as FTIR and …
Removal Of Heavy Metal Ions From Contaminated Water Using Corncob-Sulphonated Phenol Formaldehyde Condensate, Abdul–Aleem Aboul–Magd, Salwa El–Rashed, Salma Al–Zahrani
Removal Of Heavy Metal Ions From Contaminated Water Using Corncob-Sulphonated Phenol Formaldehyde Condensate, Abdul–Aleem Aboul–Magd, Salwa El–Rashed, Salma Al–Zahrani
Al-Azhar Bulletin of Science
This paper is focused on the use of agricultural by-product as a replacement of the running low cost method for removing heavy toxic and/or radioactive metal ions from water and wastewater. The modification of Egyptian corncobs as a source of low cost plant and recycling material with phenol has been developed in presence of para-formaldedhyde as a cross linking agent. The modification of corncobs was investigated to enhance their natural capacity and could be considered as an added value to the waste plant. In this study, the characterization of the synthesized sulphonated corncob–phenol formaldehyde exchange resin is described and compared …
Kinetics And Mechanism Of Oxidation Of L-Ascorbic Acid By Chromium (Vi), Mohamed Mansour
Kinetics And Mechanism Of Oxidation Of L-Ascorbic Acid By Chromium (Vi), Mohamed Mansour
Al-Azhar Bulletin of Science
The kinetics of oxidation of L-ascorbic acid by potassium chromate was studied as a function of pH, L-ascorbic acid concentration and temperature using the spectrophotometric technique. The rate of reaction is first order with respect to the concentration of each reactant and increases as [H+] increases. The kinetic data indicate involvement of the monoprotonated ascorbate species (HA-) in the redox process. A mechanism involving the formation of chromium (VI)- ascorbate intermediate is a rate-determining step followed by a redox step was suggested. The activation enthalpy and activation entropy changes for the reaction have been calculated to be ΔH*= 69 kJmol-1 …
Heavy Metals And Cyanide Removal Using Photo-Catalytic Oxidation In Galvanization Workshops, Gamal Al-Din Elkady, Mohamed Saraya, Rifaat Abdel Wahaab, Abdel-Ghany Soliman
Heavy Metals And Cyanide Removal Using Photo-Catalytic Oxidation In Galvanization Workshops, Gamal Al-Din Elkady, Mohamed Saraya, Rifaat Abdel Wahaab, Abdel-Ghany Soliman
Al-Azhar Bulletin of Science
Industrial wastewater from galvanization workshops located in meet Ghamer city at Dakahlya governorate in Egypt contains high concentrations of copper, chromium, nickel, zinc and cyanide which violating the Egyptian environmental standard. Three commercial TiO2 specimens were tested in this work namely: TiO2 Degussa P25 (80% anatase, 20% rutile), TiO2 Aldrich (100% anatase) and TiO2 Aldrich (100% rutile) and added with 0.3 ml/l hydrogen peroxide. At optimum operating conditions: TiO2 Degussa P25 photo catalyst (0.25 g l-1), 0.3 ml/l H2O2, PH =11 and temp = 298°C and time photolysis of 30 min., The results confirmed that TiO2 Degussa P25 shows the …
Synthesis, Potentiometric And Antimicrobial Studies On Metal Complexes Of Thiazole Schiff Base, Abdel-Nasser Alaghaz, Reda Ammar
Synthesis, Potentiometric And Antimicrobial Studies On Metal Complexes Of Thiazole Schiff Base, Abdel-Nasser Alaghaz, Reda Ammar
Al-Azhar Bulletin of Science
The synthesis of the Schiff base ligand salicylidene-3-phenyl-2-aminothiazole (LH2)and their Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Cd(II) metal complexes have been reported. The structure of ligand and their complexes was investigated using elemental analysis, IR, UV-Vis, 1H NMR, magnetic susceptibility and conductance measurements. Protonation constants of Schiff base and stability constants of their binary metal complexes have been determined potentiometrically in 50% DMSO–water media at 25°C and ionic strength 0.10 M sodium perchlorate. Antimicrobial activity of the ligand and metal complexes were tested using the disc diffusion method and the strains Bacillus megaterium and Candida tropicalis. The stability constants …
Interview With Wm. Brad O’Dell, Todd Skelton
Interview With Wm. Brad O’Dell, Todd Skelton
Pursuit - The Journal of Undergraduate Research at The University of Tennessee
Wm. Brad O’Dell is a 2009 UT graduate and received a B.A. in College Scholars Program with an emphasis in Structural Chemistry. College Scholars is a highly selective honors program major for students with interdisciplinary interests. Brad was also in the Chancellor’s Honors Program and received numerous accolades for his academic achievement throughout his career at the University of Tennessee, including the prestigious Barry M. Goldwater Scholarship in 2008. Brad now lives between Cambridge, UK and Bethesda, MD as a student in the National Institutes of Health-Oxford-Cambridge Graduate Partnership Program.