Experimental work was carried out to investigate the effect of fire flame (high temperature) on specimens of one way slabs using Self Compacted Concrete (SCC). By using furnace manufactured for this purpose, twenty one reinforced concrete slab specimens were exposed to direct fire flame. All of specimens have the same dimensions. The slab specimens were cooled in two types, gradually by left them in the air and suddenly by using water. After that the specimens were tested under two point loads, to study, the effect of
different: temperature levels (300ºC, 500ºC and 700ºC), and cooling rate (gradually and sudden cooling conditions) on the concrete compressive strength, modulus of rupture, flexural strength and the behavior of reinforced concrete slab specimens and comparing the results with specimens without burning (reference specimens). The results showed that, the concrete compressive strength, concrete modulus of rupture and the flexural strength decreases while the maximum (central) deflection increases with increasing the fire flame temperature. For suddenly cooled specimens the residual flexural strength is less than that of gradually cooled specimens while the deflection is greater. For slabs with 20 MPa concrete strength and gradually cooled, the residual bending strength percent is 81.5%, 75% and 62.3% ,while the increase in central deflection is 5%, 33%, and 105% at burning temperature 300ºC, 500ºC and
700ºC respectively. For suddenly cooled specimens of the same strength and exposed to the same temperatures above the residual flexural strength is 77.9%, 68.3% and 58.3% while the increase in central deflection is 25%, 52%, and 118% respectively. When the strength of concrete specimens increase, the residual flexural strength experiences small increase and the increase is of lower rate in the central deflection for 300 ºC and 500 ºC burn temperatures while the decrease is significant for 700 ºC burning temperature.
A simple chemistry method approach was used to synthesise new ligand derivate from L-ascorbic acid and its complexes. All of them were water-soluble and are used quite extensively in the medical and pharmaceutical fields. This study synthesised the new ligand derivative from L-ascorbic acid-base using the following steps: A 5,6-O-isopropylidene-L-ascorbic acid was prepared by reacting dry acetone with L-ascorbic acid followed by reacting it with trichloroacetic acid to yield [chloro(carboxylic)methylidene]-5,6-O-isopropylidene-L-ascorbic acid in the second stage. In the third stage, the derivative was reacted with (methyl(6-methyl-2-pyridylmethyl)amine to create a new ligand (ONMILA). This novel ligand was identified using a number
... Show MoreTwo Schiff bases, namely, 3-(benzylidene amino) -2-thioxo-6-methyl 2,5-dihydropyrimidine-4(3H)-one (LS])and 3-(benzylidene amino)-6-methyl pyrimidine 4(3H, 5H)-dione(LA)as chelating ligands), were used to prepare some complexes of Cr(III), La(III), and Ce(III)] ions. Standard physico-chemical procedures including metal analysis M%, element microanalysis (C.H.N.S) , magnetic susceptibility, conductometric measurements, FT-IR and UV-visible Spectra were used to identify Metal (III) complexes and Schiff bases (LS) and (LA). According to findings, a [Cr(III) complex] showed six coordinated octahedral geometry, while [La(III), and Ce(III) complexes]were structured with coordination number seven. Schiff's bases a
... Show MoreIn present work, new tetra-dentate ligand, titled 3,5-bis ((E)-5-Bromo-2-hydroxy benzylidene amino) benzoic acid (H3L), was prepared via an acid-catalyzed condensation process. New four metallic ligand complexes with Co(II), Ni(II), Cu(II) and Zn(II) ions, were also prepared from the refluxing of equivalent moles. Ligand's structure and its complexes; were confirmed by numerous characterization methods, including Ultraviolet-Visible, Infrared, Mass Spectrometer, 1H and 13C Nuclear Magnetic Resonance spectra, atomic absorption, magnetic moments, and molar conductivity measurements. The results of the spectroscopic analyzes proved that the prepared ligand acts as tetradentate bi-ionic ligand and it was bond
... Show MoreA new Schiff base (HL2) ligand (4‐{2‐[(2‐hydroxy‐benzylidene)‐amino]‐ethyl}‐benzene‐1,2‐diol) has been synthesized by condensing of 4‐(2‐amino‐ethyl)‐benzene‐1,2‐diol and 2‐hydroxy‐benzaldehyde. In turn, its transition metal complexes were prepared, having the following general formulas: Ni(L2)2, Pd(L2)2, and Pt(L2)22Cl. The prepared ligand and its metal complexes Ni(II), Pd(II), and Pt(IV) have been characterized by Fourier transform infrared (FTIR) spectra, proton nuclear magnetic resonance (1H‐NMR
2-benzamide benzothiazole complexes of Pd(II) , Pt(IV) and Au(III) ions were prepared by microwave assisted radiation. The ligand and the complexes were isolated and characterized in solid state by using FT-IR, UV-Vis spectroscopy, flame atomic absorption, elemental analysis CHNS , magnetic susceptibility measurements , melting points and conductivity measurements. The nature of complexes in liquid state was studied by following the molar ratio method which gave results approximately identical to those obtained from isolated solid state; also, stability constant of the prepared complexes were studied and found that they were stable in molar ratio 1:1.The complexes have a sequar planner geometry except Pt(IV) complex has octahedral .
... Show MoreBackground/aim: The rising challenge of microbial resistance necessitates the development of novel therapeutic agents. This study aims to synthesize, characterize, and evaluate the antimicrobial potential of a new series of mixed-ligand metal complexes (ZnII, CuII, NiII, and MnII) derived from a p-hydroxybenzaldehyde-4-aminoantipyrine Schiff base and 2,2′-bipyridine, in addition to assessing the binding affinity and pharmacokinetic properties of the synthesized free Schiff base ligand through molecular docking and ADME profiling. Methods: The Schiff base ligand and its transition metal complexes were synthesized and subsequently characterized using single-crystal X-ray diffraction, elemental analysis, FTIR, UV–Vis spectroscopy, NMR, mag
... Show MoreThis study was conducted to determine the ability of water treatment system (Vortisand) to reduce some chemical and physical properties for tigris river raw water, It consisted of turbidity, electrical conductivity, pH, total hardness, calcium Hardness as well as temperature in order to determine the unit`s efficiency for reducing their concentration as compared to those in the water produced by some classical potable water projects (Dora and Wathba) in Baghdad. Samples were collected during the cold months (December 2016 and January 2017) and during the hot months (May and June 2017). The results showed that this system has the ability to reduce some properties such as turbidity, the values were 215NTU in raw water and decreased to NTU
... Show MoreAnew Schiff base (NaHL) has been prepared from the reaction between the salt of amino acid glycine with 2-hydroxy naphthaldehyde. By tridentate Schiff base of (ONO), donors were characterized by using U.V and spectrophotometer techniques. Complexes of Co(II) Ni(II) Cu(II) and Zn(II) ion with the ligand have been prepared, these complexes were identified by infrared, electronic spectral data, elemental analysis, magnetic moments, and molar conductivity measurements. It is concluded from the elemental analysis that all the complexes have (1:2) [metal:ligand] molar ratios, octahedral, with the exception to Zn(II) complex which have (1:1)[metal:ligand] molar ratio.
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