Previously, many empirical models have been used to predict corrosion rates under different CO2 corrosion parameters conditions. Most of these models did not predict the corrosion rate exactly, besides it determined effects of variables by holding some variables constant and changing the values of other variables to obtain the regression model. As a result the experiments will be large and cost too much. In this paper response surface methodology (RSM) was proposed to optimize the experiments and reduce the experimental running. The experiments studied effects of temperature (40 – 60 °C), pH (3-5), acetic acid (HAc) concentration (1000-3000 ppm) and rotation speed (1000-1500 rpm) on CO2 corrosion performance of the regression model calculated by RSM. The experiments were conducted in saturated solution of CO2 with 3.5 % NaCl solution. STATISTICA program version 10 was used for data analysis. In conclusion a quadratic model is proposed to predict the effect of mentioned variables in CO2 environment.
Hydrochloric acid (HCl) is a substance that is frequently utilized in industrial operations for important tasks such as chemical cleaning and pickling metallic surfaces.Therefore, the corrosion inhibition ability of three newly synthesized quinazoline derivatives namely, 3-allyl-2-(propylthio) quinazolin-4(3H)-one) (APQ), (3-allyl-2-(allylthio) quinazolin-4(3H)-one) (AAQ), (3-allyl- 2-( Prop -2-yn -1-ylthio) Quinazolin - 4 (3H) - one) (AYQ) were theoretically determined and these compounds were characterized using Fourier Transform Infra-Red (FTIR) and 1H and 13C Nuclear Magnetic Resonance (NMR) spectroscopic. A series of quantum chemical properties of these derivatives: EHOMO, ELUMO, energy gap (ΔE),dipole moment (μ), hardness (η), soft
... Show MorePseudomonas aeruginosa was isolated from various clinical samples included urine, sputum, stool, ear, wound & burn swabs. Detection of the ability of local isolates to produce staphylolysin enzyme was studied, on Tryptic soya agar + 0.2% (wt./vol.) of heat killed Staphylococcus. aureus at temperature 100oC. medium and the diameters of lysis zone ranged from 5-22mm, then the isolate P16 was chosen to extract staphylolysin A (LasA) and its specific activity reaches 8.59 unit /mg protein, whi1e the isolate P5 was chosen to extract staphylolysin D (LasD) where it's specific activity reaches 0.66 unit /mg protein since the two isolates were the most production of enzyme. Staphylolysin enzyme was extracted by cooling centrifugation and par
... Show MoreIn this study, detection of uricase production from Pseudomonas aeruginosa
isolates was done by applying colorimetric method, Uricase was purified from the
most potent isolate by precipitation using ammonium sulphate (80% saturation) then
purification was achieved using DEAE –Cellulose ion exchange and Sepharose 6B
gel filtration chromatography column, 16.4% of total enzyme was recovered with
specific activity 2337.5U/mg and 22.21folds of purification. Characterization of
uricase involved detection of optimal conditions for uricase activity, the maximal
activity was obtained at temperature 45ºC,while uricase appeared to be stable at
40ºC. Uricase showed optimal activity at pH 9 while pH stability was in the
The objective of this study was to isolate and identify the asparaginase-producing bacteria, then purify and characterize the enzyme in order to investigate their properties in the future. Fifteen local bacterial isolates were isolated from various sites in the city of Baghdad, identified by conventional morphological and biochemical procedures, and confirmed using vitek 2 methods, and submitted to primary screening processes for asparaginase production. For secondary screening, eight isolates with the greatest yellow zone ability on a specific solid medium were chosen. Bacillus sp. was reported to have the highest enzyme production (7.5 U/mg proteins). After 24 hours of incubation, submerged fermentation yielded optimal conditi
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Radial density distribution function of one particle D(r1) was calculated for main orbital of carbon atom and carbon like ions (N+ and B- ) by using the Partitioning technique .The results presented for K and L shells for the Carbon atom and negative ion of Boron and positive ion for nitrogen ion . We observed that as atomic number increases the probability of existence of electrons near the nucleus increases and the maximum of the location r1 decreases. In this research the Hartree-fock wavefunctions have been computed using Mathcad computer software .
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study was conducted on a stretch of Tigris river crossing Baghdad city to determine the concentration of some chlorophenols pollutants. Aqueous samples were preliminary enriched about 500 times and the chlorophenols have determined using high performance liquid chromatography HPLC. Limits of detection LOD were (0.007–0.012 mg L-1), relative standard deviations RSD% were 2.4%–5.59% and relative recoveries were 51.06%– 104.07%. The existence of chlorophenols in Tigris river was in the range 0.023–4.596 mg L-1. The developed method suggested in this study can be applied for routine analysis and monitoring of chlorinated phenols in environmental aqueous samples.
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The special core analysis tests were accomplished on a set of core plugs for Mishrif Formation (mA, mB1, and mB2cde/mC units) in West Qurna/1 oilfield, southern Iraq. Oil relative permeability (Kro) data and the Corey-type fit of the data as functions of the brine saturation at the core outlet face for individual samples in the water-oil imbibition process to estimate relative permeability measurements by the centrifuge method were utilized. Identical correlations for oil and water relative permeabilities were extracted by steady-state and unsteady-state methods. For the mA samples, the gas-water capillary pressure curves were within a narrow range (almost identical) indicating that mA is a homogeneous unit. Kro curves for three mB2
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The special core analysis tests were accomplished on a set of core plugs for Mishrif Formation (mA, mB1, and mB2cde/mC units) in West Qurna/1 oilfield, southern Iraq. Oil relative permeability (Kro) data and the Corey-type fit of the data as functions of the brine saturation at the core outlet face for individual samples in the water-oil imbibition process to estimate relative permeability measurements by the centrifuge method were utilized. Identical correlations for oil and water relative permeabilities were extracted by steady-state and unsteady-state methods. For the mA samples, the gas-water capillary pressure curves were within a narrow range (almost identical) indicating that mA is a homogeneous unit. Kro curves for thr
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The compound 3-[4Ì„-(4Ë-methoxy benzoyloxy) benzylideneamino]-2-thioxo-imidazolidine-4-one [III] was prepared from the cyclization of thiosemicarbazone [II] with
ethyl α -chloroacetate in the presence of fused sodium acetate. Treatment the later compound
with acetic anhydride yielded the corresponding 1-Acetyl-3-[ 4Ì„- (4Ë- methoxy benzoyloxy)
benzylideneamino] – 2 – thioxo -imidazolidine-4-one [IV]. 1,3-Oxazepine derivatives [V]a-d
and [VI]a-d are obtained from the reaction of compounds[III] and [IV] with different acid
anhydrides, in dry benzene. The FTIR and
1
HNMR spectroscopy are indicated a good
evidence for the formation of the synthesized compounds. Some of the synthesized